Question

Enter your answer and show all the steps that you use to solve this problem in the space provided
Solve the system of equations algebraically. Show all of your steps.
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Answer 1

Answer: x = -4, x = 5

Step-by-step explanation:

You can use the substitution method for this problem.

y = $x^{2}$ + 2x, but y also = 3x +20.

Because of this, you can determine that $x^{2}$ +2x = 3x + 20 because they are both equal to the same thing, y.

Solve the quadratic equation you got from substitution:

$x^{2}$ + 2x = 3x + 20

$x^{2}$ -x = 20

$x^{2}$ -x -20 = 0

You can factor this equation:

(x+4)(x-5) = 0

x = -4, x = 5