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What are the ordered pairs of the solutions for this system of equations? y=x^2-8 and y=2x

User Adarsh Mohan
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1 Answer

27 votes
27 votes

Answer:

4, 8) and (-2, -4)

Explanation:

y = x² - 8 and y = 2x .

Substitute y = 2x into the first equation.

2x = x² - 8

0 = x² - 2x - 8 Add -2x to both sides.

0 = ( x - 4)(x + 2) Factor

0 = x - 4 ; 0 = x + 2

x = 4 ; x = - 2

Solve y = 2x when x = 4 solve y = 2x when x = -2

y = 2(4) y = 2(-2)

y = 8 y = -4

(4, 8) and (-2, -4)

User Goblinjuice
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