Question

Y = x^2-3
8x - y = 18​

Answer 1

When x=5, y=22. And when x=3, y=6.

Explanation:

y=x^2-3

8x-y=18

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y=8x-18

x^2-3=8x-18

x^2-8x-3=-18

x^2-8x-3-(-18)=0

x^2-8x-3+18=0

x^2-8x+15=0

factor out the trinomial,

(x-5)(x-3)=0,

zero property

x-5=0, x-3=0,

x=0+5=5

x=0+3=3

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y=5^2-3=25-3=22

y=3^2-3=9-3=6