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3 years ago

Which are steps that could be used to solve 0 = 9(x2 + 6x) – 18 by completing the square? Check all that apply.

2 answers:

8 0

18 + 81 = 9(x²<span> + 6x + 9)
</span><span>11 = (x + 3)</span>²

When we are completing the square, we are going to move the value of c across the equals. We will do that by adding, and end up with

18=9(x²+6x)

We take the value of b (the coefficient of x), divide it by 2 and square it:
(6/2)²=3²=9

This is the value that completes the square. However, since the entire square is multiplied by 9, this value must be multiplied by 9 before we can add it across the equals:
18+9(9) = 9(x²+6x+9)
18+81=9(x²+6x+9)
99=9(x²+6x+9)

Dividing both sides by 9, we have:
11=x²+6x+9

11=(x+3)²

tankabanditka [31]3 years ago

7 0

1st and 4th would be the correct answer to the quaestion

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What is 0.26 repeating made into a decimal

Savatey [412]

It already is a decimal unless you mean a repeating decimal, it would be .26 with a line over the number.

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3 years ago

1. Three friends pooled their money to purchase a new game system that costs $298. One person

iragen [17]

Answer:

First person: $107

Second person: $98

Third person: $93

Step-by-step explanation:

Let be "f" the amount of money (in dollars) that the first person contributed to the purchase, "s" the amount of money (in dollars) that the second person contributed to the purchase and "t" the amount of money (in dollars) that the third person contributed to the purchase.

With the information given in the exercise, you can set up the following equations:

Equation 1 → $f+s+t=298$

Equation 2 → $s=f-9$

Equation 3 → $t=f-14$

Substitute the Equations 2 and 3 into the Equation 1 and then solve for "f":

$f+(f-9)+(f-14)=298\\\\3f-23=298\\\\f=\frac{321}{3}\\\\f=107$

Finally, substitute the value of "f" into the Equation 2 and then into the Equation 3, in order to find the values of "s" and "t".

Therefore, you get:

$s=107-9\\\\s=98\\\\\\t=107-14\\\\t=93$

5 0

3 years ago

Whats the distance between (-8,-7) (8,-4)

balandron [24]

To find the distance between points, use the distance formula.

Distance formula: $\sqrt{ (x_{2} - x_{1})^{2} + ( y_{2} - y_{1})^{2} }$

Plug in your values for $x_{2}, x_{1}, y_{2}, y_{1}$ using (-8, -7) and (8, -4) and solve.

$\sqrt{(8 - (-8))^{2}+(-4 - (-7))^{2}}$
$\sqrt{(8+8)^{2}+(-4+7)^{2}}$
$\sqrt{(16)^{2}+(3)^{2}}$
$\sqrt{256+9}$
$\sqrt{265}$ ≈ $16.28$

Answer:
Approximately 16.28 units.

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3 years ago

14 is 7 times a number c

Stolb23 [73]

Answer:

c = 2

Step-by-step explanation:

From the statement we have that If 14 is 7 times a number c, we can write the following equation:

7c = 14. Solving for c, we have:

c = 14/7 = 2

3 0

2 years ago

Select all the situations that describe adding or subtracting opposites to make zero.

jeka94

It would be option number 3 and option number 4

4 0

2 years ago

Read 2 more answers