Question 1013112
Using y for f(x):
when x=-1, y=3
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y=mx+b
3=-m+b
b=3+m Use this to substitute for b below.
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When x=2, y=9
y=mx+b
9=2m+b Substitute for b from above.
9=2m+(3+m)
9=3m+3
6=3m
2=m
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b=3+m=3+2=5
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y=mx+b
y=2x+5
ANSWER: f(x)=2x+5
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CHECK:
f(-1)=2(-1)+5
3=-2+5
3=3
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f(2)=2(2)+5
9=4+5
9=9
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