2 years ago

Solve the system of equations: y=2x y=x²-8

1 answer:

6 0

Set equal to each other
x^2 - 8 = 2x
x^2 - 2x - 8 = 0

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

Plug in 4
y = 2x or y = x^2 - 8
y = 2(4) or y = 4^2 - 8
y = 8

Plug in -2
y = 2x or y = x^2 - 8
y = 2(-2) or y = (-2)^2 - 8
y = -4

There are two solutions
(4, 8) and (-2, -4)

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