Answer:
When x=5, y=22. And when x=3, y=6.
Step-by-step 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
