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3 years ago

When solving the equation x2 – 8x - 7 = ( by completing

2 answers:

8 0

X^2-8x-7=0
Add 7 to both sides
X^2-8x=7
Now use formula
(B/2a)^2
(-8/2)^2= 16
Add 16 to left subtract from right to get
X^2-8x+16=-9
Now factor into
(X-4)^2=-9
For your final answer

Ivenika [448]3 years ago

5 0

Step-by-step explanation:

x²– 8x - 7 = 0

(x²-8x+16) -7 = 16

(x²-8x+16) = 16+7

(x-4)² = 23

x-4 = √23

so x= 4+√23 or x= -4√23

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The average rate of change from x = -2 to x = 6 for the function shown in the graph is______?

WITCHER [35]

Answer: -1/2

Step-by-step explanation:

3 0

3 years ago

What is the factored form of the expression?<br><br> d^2 = 36d + 324

Veseljchak [2.6K]

Answer:

$(x-43.45)(x+7.45)=0$

Step-by-step explanation:

We have the quadratic equation $d^{2}=36d+324$ i.e. $d^{2}-36d-324=0$

As, the roots of the quadratic equation $ax^{2}+bx+c=0$ are given by $x=\frac{-b\pm \sqrt{b^{2}-4ac}}{2a}$ .

So, from the given equation, we have,

a = 1, b = -36 , c = -324.

Substituting the values in $x=\frac{-b\pm \sqrt{b^{2}-4ac}}{2a}$ , we get,

$x=\frac{36\pm \sqrt{(-36)^{2}-4\times 1\times (-324)}}{2\times 1}$

i.e. $x=\frac{36\pm \sqrt{1296+1296}}{2}$

i.e. $x=\frac{36\pm \sqrt{2592}}{2}$

i.e. $x=\frac{36\pm 50.9}{2}$

i.e. $x=\frac{36+50.9}{2}$ and $x=\frac{36-50.9}{2}$

i.e. $x=\frac{86.9}{2}$ and $x=\frac{-14.9}{2}$

i.e. x = 43.45 and x = -7.45

Thus, the roots of the equation are 43.45 and -7.45.

Hence, the factored form of the given expression will be $(x-43.45)(x+7.45)=0$

3 0

3 years ago

Reduce 36/45 to lowest terms and write the denominator in the blank.

Firlakuza [10]

Answer:

4/5

Step-by-step explanation:

Step 1:

36/45 = 12/15

Step 2:

12/15 = 4/5

Answer:

4/5

Hope This Helps :)

5 0

4 years ago

Read 2 more answers

Write a quadratic equation in standard form that has two solutions, -9 and 3

erastovalidia [21]

So for this you need the two solutions to be x= -9 and x=3 then move over the numbers and put in brackets (x+9)(x-3) then multiply together x^2+9x-3x-27 then combine like terms to get x^2+6-27

8 0

3 years ago

3x=9y find slope and intercept

miv72 [106K]

Slope = ⅓
y-intercept = 0
x-intercept = 0

7 0

3 years ago