Answer:
X=4 or X=-2
Step-by-step explanation:
Step-1 : Multiply the coefficient of the first term by the constant 1 • -8 = -8
Step-2 : Find two factors of -8 whose sum equals the coefficient of the middle term, which is -2 .
-8 + 1 = -7
-4 + 2 = -2 That's it
Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -4 and 2
x2 - 4x + 2x - 8
Step-4 : Add up the first 2 terms, pulling out like factors :
x • (x-4)
Add up the last 2 terms, pulling out common factors :
2 • (x-4)
Step-5 : Add up the four terms of step 4 :
(x+2) • (x-4)
Which is the desired factorization
Equation at the end of step
1
:
(x + 2) • (x - 4) = 0
STEP
2
:
Theory - Roots of a product
2.1 A product of several terms equals zero.
When a product of two or more terms equals zero, then at least one of the terms must be zero.
We shall now solve each term = 0 separately
In other words, we are going to solve as many equations as there are terms in the product
Any solution of term = 0 solves product = 0 as well.
Solving a Single Variable Equation:
2.2 Solve : x+2 = 0
Subtract 2 from both sides of the equation :
x = -2
Solving a Single Variable Equation:
2.3 Solve : x-4 = 0
Add 4 to both sides of the equation :
x = 4
Supplement : Solving Quadratic Equation Directly
Solving x2-2x-8 = 0 directly
Earlier we factored this polynomial by splitting the middle term. let us now solve the equation by Completing The Square and by using the Quadratic Formula
Parabola, Finding the Vertex:
3.1 Find the Vertex of y = x2-2x-8
Parabolas have a highest or a lowest point called the Vertex . Our parabola opens up and accordingly has a lowest point (AKA absolute minimum) . We know this even before plotting "y" because the coefficient of the first term, 1 , is positive (greater than zero).
Each parabola has a vertical line of symmetry that passes through its vertex. Because of this symmetry, the line of symmetry would, for example, pass through the midpoint of the two x -intercepts (roots or solutions) of the parabola. That is, if the parabola has indeed two real solutions.
Parabolas can model many real life situations, such as the height above ground, of an object thrown upward, after some period of time. The vertex of the parabola can provide us with information, such as the maximum height that object, thrown upwards, can reach. For this reason we want to be able to find the coordinates of the vertex.
For any parabola,Ax2+Bx+C,the x -coordinate of the vertex is given by -B/(2A) . In our case the x coordinate is 1.0000
Plugging into the parabola formula 1.0000 for x we can calculate the y -coordinate :
y = 1.0 * 1.00 * 1.00 - 2.0 * 1.00 - 8.0
or y = -9.000
Parabola, Graphing Vertex and X-Intercepts :
Root plot for : y = x2-2x-8
Axis of Symmetry (dashed) {x}={ 1.00}
Vertex at {x,y} = { 1.00,-9.00}
x -Intercepts (Roots) :
Root 1 at {x,y} = {-2.00, 0.00}
Root 2 at {x,y} = { 4.00, 0.00}
Solve Quadratic Equation by Completing The Square
3.2 Solving x2-2x-8 = 0 by Completing The Square .
Add 8 to both side of the equation :
x2-2x = 8
Now the clever bit: Take the coefficient of x , which is 2 , divide by two, giving 1 , and finally square it giving 1
Add 1 to both sides of the equation :
On the right hand side we have :
8 + 1 or, (8/1)+(1/1)
The common denominator of the two fractions is 1 Adding (8/1)+(1/1) gives 9/1
So adding to both sides we finally get :
x2-2x+1 = 9
Adding 1 has completed the left hand side into a perfect square :
x2-2x+1 =
(x-1) • (x-1) =
(x-1)2
Things which are equal to the same thing are also equal to one another. Since
x2-2x+1 = 9 and
x2-2x+1 = (x-1)2
then, according to the law of transitivity,
(x-1)2 = 9
We'll refer to this Equation as Eq. #3.2.1
The Square Root Principle says that When two things are equal, their square roots are equal.
Note that the square root of
(x-1)2 is
(x-1)2/2 =
(x-1)1 =
x-1
Now, applying the Square Root Principle to Eq. #3.2.1 we get:
x-1 = √ 9
Add 1 to both sides to obtain:
x = 1 + √ 9
Since a square root has two values, one positive and the other negative
x2 - 2x - 8 = 0
has two solutions:
x = 1 + √ 9
or
x = 1 - √ 9
Solve Quadratic Equation using the Quadratic Formula
3.3 Solving x2-2x-8 = 0 by the Quadratic Formula .
According to the Quadratic Formula, x , the solution for Ax2+Bx+C = 0 , where A, B and C are numbers, often called coefficients, is given by :
- B ± √ B2-4AC
x = ————————
2A
In our case, A = 1
B = -2
C = -8
Accordingly, B2 - 4AC =
4 - (-32) =
36
Applying the quadratic formula :
2 ± √ 36
x = —————
2
Can √ 36 be simplified ?
Yes! The prime factorization of 36 is
2•2•3•3
√ 36 = √ 2•2•3•3 =2•3•√ 1 =
± 6 • √ 1 =
± 6
So now we are looking at:
x = ( 2 ± 6) / 2
Two real solutions:
x =(2+√36)/2=1+3= 4.000
or:
x =(2-√36)/2=1-3= -2.000
Which equation best represents the line?
y = 3x + 3
y = 1/2x − 3
y = 1/2x + 3
y = 3x + 1/2
Answer:
the third one, y = 1/2x + 3
Answer:
y = 1/2x + 3
Step-by-step explanation:
The y intercept is 3 and the slope is 1/2.
HELP QUICKKK
Car A is traveling east at a steady speed of 60 miles per hour. After 2 hours, it is 130 miles east of Johnstown. Car B is traveling east on the same road. Its distance east of Johnstown is represented by the graph. Where were the two cars in relation to each other when they began traveling? A. Car A was 10 miles east of car B. B. Car A was 60 miles east of car B. C. Car B was 20 miles east of car A. D. Car B was 10 miles east of car A
Answer:
D. Car B was 10 miles east of car A
Step-by-step explanation:
→ Work out how many miles car A travelled
130
→ Work out how many miles car B travelled in 2 hrs
120
→ Find the difference
Car A is bigger by 10 miles
Answer:
Car A was 10 miles east of car B
Please give Examples for real life examples for expressing very small number sin standard form.
Mr. Smith's class has collected 72 cans in a food drive. They plan to sort the cans into bags, with an equal number of cans in each bag. Write an expression to show how many cans there will be in each bag.
Answer:
C
Step-by-step explanation:
They are dividing the number of cans in to x bags equally.
Answer:
C
Step-by-step explanation:
Its c because your finding how many cans are in each bag so you will divide cans by bags. For example 72/8=9 bags
Solve for x.
7/8 = x/16
Answer:
X=16*7/8= 14. by multiplying. 16 *7/8
(PLEASE HELP, BRAINLIEST IF CORRECT) A cylinder and a cone have the same base and altitude. If the volume of the cone is 30 cubic inches, what is the volume of the cylinder?
Choices:
A. 10 Cubic Inches
B. 15 Cubic Inches
C. 30 Cubic Inches
D. 60 Cubic Inches
E. 90 Cubic Inches
Stella models a product with algebra tiles. Write a number sentence that best describes her model. Fill in the blanks.
Answer:
Sorry i dont understand
Step-by-step explanation:
Answer:
the model represents (10)(5) = 50 but when reversed (-10)(5) it equals -50
Step-by-step explanation:
hope this helps!
PLz help me! We r doing semester finals and i need to get this lesson finished in 2 hours so i can get my grade up!
Answer:
$84
Step-by-step explanation:
1. If 20% is marked off, then you are selling it for 80%.
2. 455 * 80% = 364
3. Since you are finding the cost markup from 280, then 364-280=84
Find the GCF of 6 and 18.
Answer:
6
Step-by-step explanation:
6x1 = 6, 6x3 = 18
Answer:
The GFC of 6 and 18 is 6
Step-by-step explanation:
6 = 1, 2, 3, 6
18 = 1, 2, 3, 6, 9, 18
*Number that divides both 6 and 18 is 6*
___________________
Hope it helps!
Have a good day!
which set of integers is in the correct order, from Least to greatest?
A. |-8|, 4, -3, 0,1.
B. 0, 1, -3, 4, |-8|.
C. -3, 0, 1, 4, |-8|.
D. |-8|, -3, 0, 1, 4.
5/7 of __ is 1/7 plz help asap
[tex]\dfrac 57 x = \dfrac 17 \\\\\implies 5x =1 \\\\\implies x = \dfrac 15 \\\\\\\text{Hence }~ \dfrac 57 ~ \text{of}~ \dfrac 15 ~ \text{is }~\dfrac 17[/tex]
Answer:
1/5
Step-by-step explanation:
'of' is the same as multilpy
5/7 × ? = 1/7
? = 1/7 ÷ 5/7
? = 1/7 × 7/5 = 7/35
?=7/35
? = 1/5
check answer:
5/7 of 1/5 = 5/7 ×1/5 = 5/35 = 1/7
Evaluate {3^4}{3^2}
for brainliest plz help me
Answer:
3^4 x 3^2 = 729
Step-by-step explanation:
Answer:
[tex](3^4)*(3^2)=729[/tex]
Hope this helps.
You buy 3.18 pounds of apples, 1.25 pounds of pears, and 2.67 pounds of oranges. What is your total bill rounded to the nearest cent?
Answer:
318125267
Step-by-step explanation:
-_-...............that is the answer
3.17 pounds of apples
1.25 pounds of pears2
2.56 pounds of oranges
add = 7.98
rounded = 7.42, (or anything close. I am really bad at rounding decimals)
Last two plz help!!(ty for all the help) :
14. Factor the following:
I. b2 + b - 12
j. k2 - 5k + 6
Answer:
I= (b-3) (b+4) J= (k-3) (k-2) :)
Step-by-step explanation:
Answer:
I. (B^2 + B -12) is (b-3)(b+4)
J. K^2 -5K + 6 is (k-3)(k-2)
Hope this helps
- Andrew
What is the slope of this line?
A.) −3/4
B.) 3/4
C.) −4/3
D.) I don't know.
This is really urgent
Answer:
its (18-0) ,
Step-by-step explanation:
by using 17 +1 = 18
Jordan bikes at a speed of 8 2/3 mph. How many miles will he bike in 2/3 of an hour?
Answer:
26.87 miles
Step-by-step explanation:
Answer: 5 7/9
Step-by-step explanation:
Ingrid spends $120 on car repairs. Which integer represents the amount of money Ingrid must earn in order to create a zero pair?
–240
–120
120
240
Answer: -120
Step-by-step explanation:
this would be the answer because if you take a positive and add it to a negative you get zero if their the additive inverse of the number.
Kenzie buys hair scrunchies. The cost for 20 scrunchies is $3.00.
The cost, c, for scrunchies is proportional to the number, n, of scrunchies.
Create an equation using n and c.
Kenzie can buy 48 Scrunchies
Step-by-step explanation:
You have to divide 3 by 20. (3/20) Which is also 1.5/10 and as a decimal, that is 15 cents. So one scrunchie is equivalent to 15 cents, which means how many times can you take .15 from 7.25 is how many scrunchies she can buy. So how many times does .15 go into 7.25? The answer is 48.3(repeating). So you have to round it down because if you round it up she needs more money.
The ratio of the interior angle measures of a triangle is 2:3:5. What are the angle measures?
In order from the smallest angle to the largest angle, the angle measures are __°, __°, and __°.
Show all steps.
Answer:
36:54:90
Step-by-step explanation:
you add all the parts together (2+3+5) which is 10. then you divide 180 by 10 because angles in triangle add up to 180. so 18 is one part
then you just times 18 by each part in the ratio
PLEASE HELP ME I AM ON A TEST PLEASE!!!!!!!!!!!!
the first screenshot is the top of the page
the second is the bottom of the page
Answer:
1st. Add 5 each time so 5 times 12 = 60 so
5
10
15
20
25
30
35
40
45
50
55
60
2: H = 5M
Step-by-step explanation:
Answer:
5 457
Step-by-step explanation:
Solve for x. Round to the nearest tenth, if necessary.
Answer:
[tex]\sqrt19[/tex]
Step-by-step explanation:
First we solve for the biggest triangle: using the Pythagorean theorem, (a^2 + b^2 = c^2) we put in the sides,
9^2 + b^2 = 10^2.
solve, 81 + b^2 = 100
then we subtract 81 from both sides. b^2 = 19, and the answer is [tex]\sqrt 19[/tex].
Now we know what the third side is, which is the hypotenuse for the smaller triangle, so we use the Pythagorean theorem again.
4^2 + x^2 = 19.
Solve
16 + x^2 = 19
Subtract 16 from both sides
x^2 = 19
and finally, we take the square root of both sides
x = [tex]\sqrt19[/tex]
10 divided by 2 pa answer po grade 3 po ako
Answer:
10 divided 2 is 5 this is correct
Step-by-step explanation:
hope it help
I have a picture of my question please answer this
Thanks a lot for all your help
Answer:
12p = 420
Step-by-step explanation:
Im so lost i dont get it
Vanessa and Zack are playing a game where the player with the lower score wins. At the end of the game, Vanessa has a score of Negative 3 and StartFraction 5 over 8 EndFraction and Zack has a score of Negative 3 and two-thirds. Which statement explains who won?
Comparing the decimal equivalents of their scores shows that Vanessa won because –3.625 is less than Negative 3.ModifyingAbove 6 with bar.
Comparing the decimal equivalents of their scores shows that Vanessa won becauseNegative 3.ModifyingAbove 6 with bar is less than –3.625.
Comparing the decimal equivalents of their scores shows that Zack won because –3.625 is less than Negative 3.ModifyingAbove 6 with bar.
Comparing the decimal equivalents of their scores shows that Zack won becauseNegative 3.ModifyingAbove 6 with bar is less than –3.625.
Answer:
Answer: Zack won. If you compare the decimal equivalents of their scores, -3.666 < -3.625
Step-by-step explanation:
Given: Vanessa and Zack are playing a game where the player with the lower score wins.
Score of Vanessa=
Score of Zack =
We can see
⇒ Zack has the lower score .
Hence, Zack won. If you compare the decimal equivalents of their scores, -3.666 < -3.625.
D=answer
Can anybody help me with this question and show me how to do it step by step, ASAP?! Btw, this question is for solving systems by elimination. I really need to sleep, and I just want to get a good grade on this.
Carl bought 19 apples of 2 different varieties to make a pie. The total cost of the apples was $5.10. Granny Smith apples cost $0.25 each and Gala apples cost $0.30 each. How many of each type of apple did Carl buy?
Answer:
Step-by-step explanation:
Split 19 into 2, since Carl bought two types of apples.
19/2 = 9.5
0.25 x 9 = 2.25
0.3 x 9 = 2.7
2.25 + 2.7 = 4.95
5.10 - 4.95 = 0.15
0.3 x 8 = 2.4
2.25 + 2.4 = 4.65
5.1 - 4.65 = 0.45
Pls answer it i will give brainly and no links pls ty worth 29 points
Answer:
7.5mph (1 d.p)
Step-by-step explanation:
First, I worked out what a third of an hour was to match the unit mph.
60 minutes / 3 = 20 mins
A third of an hour is 20minutes so two thirds of an hour is 40 minutes.
But as we know, one third as a decimal is 0.33(reccuring) so therefore two thirds as a decimal is 0.66, which we need to use.
Now, we need to remember the equation. Speed = distance / time
Place the facts we already know in place.
speed = 5miles / 0.66 (using a calculator.)
speed = 7.5mph (1 d.p)
Hope this helps and you have a good day!
please help me with this question !
HELP MEEEEEE PLEASE<3
In 1 7/8 days, a construction crew built 2 3/4
miles of road.
What is the unit rate in miles per day?
Answer:
3 3/5 miles
Step-by-step explanation:
6 3/4 divided by 1 7/8=
3 3/5