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zavuch27 [327]
4 years ago
8

X^2+4x=7 using the quadratic formula?

Mathematics
1 answer:
Eva8 [605]4 years ago
6 0
When you have
ax^2+bx+c=0
x=\frac{-b+/- \sqrt{b^{2}-4ac} }{2a}


1x^2+4x=7
minus 7
1x^2+4x-7=0
a=1
b=4
c=-7
sub

x=\frac{-4+/- \sqrt{4^{2}-4(1)(-7)} }{2(1)}
x=\frac{-4+/- \sqrt{16+28} }{2}
x=\frac{-4+/- \sqrt{44} }{2}
x=\frac{-4+/- 2\sqrt{11} }{2}
x=-2+/- \sqrt{11}

x=-2+ \sqrt{11} or -2- \sqrt{11}

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Wat is <br><br> $3.459B<br> 2.443B<br> $55.838B<br> 85.965B <br> in dollars pls
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Answers:

$3,459,000,000

$2,443,000,000

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8 0
3 years ago
Solve by elimination:
Pie

Answer:

B (5, 13)

Step-by-step explanation:

9x + 4y = 97

9x + 6y = 123

To solve by elimination, we want to <em>eliminate</em> a variable. To do this, we must make one variable cancel out.

First, we can see that both equations have 9x. To cancel out x, we must make <em>one</em> of the 9x's <em>negative</em>. To do this, multiply <em>each term</em> in the equation by -1.

-1(9x + 6y = 123)

-9x - 6y = -123

This is one of your equations. Set it up with your other given equation.

9x + 4y = 97

-9x - 6y = -123

Imagine this is one equation. Since every term is negative, you will be subtracting each term.

9x + 4y = 97

-9x - 6y = -123

___________

0x -2y = -26

-2y = -26

To isolate y further, divide both sides by -2.

y = 13

Now, to find x, plug y back into one of the original equations.

9x + 4(13) = 97

Multiply.

9x + 52 = 97

Subtract.

9x = 45

Divide.

x = 5

Check your answer by plugging both variables into the equation you have not used yet.

-9(5) - 6(13) = -123

-45 - 78 = -123

-123 = -123

Your answer is correct!

(5, 13)

Hope this helps!

6 0
3 years ago
What is the proper equation <br> (-5cd^-4)(2cd^2)^2
mojhsa [17]

Answer:

-20c^3

Step-by-step explanation:

((−5c)(d−4))((2cd2)2)

= −20c3d4 /d4

=-20c^3

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Timothy and his brothers are selling lemonade and cookies to raise funds for a camping trip. Paul bought two cups of lemonade an
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Answer:

im try ing to think

Step-by-step explanation:

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3 years ago
Jeremy wants to buy a new computer, the sales woman says he can make down payments and then pay for the computer in installments
Llana [10]
X=t-yz   and we are asked to solve for y so, subtract t from both sides

x-t=-yz  divide both sides by -z

(x-t)/(-z)=y

y=(x-t)/(-z)  multiply the numerator and denominator by -1

y=(t-x)/z
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3 years ago
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