Slope intercept form equation:
y=mx+C
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We already know that m=-4. Now, let's find the value of C.
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m=-4, and when x=-1, y=5.
(5)=(-4)*(-1)+C
5=4+C
5-4=4+C-4
1=C
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Therefore the slope intercept form of the function is:
y=-4x+1