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Write a linear Write a linear function f with f(−9)=10 and f(−1)=−2.function f with f(−9)=10 and f(−1)=−2.

User Ranu
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1 Answer

4 votes

The point-slope form:


y-y_1=m(x-x_1)\\\\m=(y_2-y_1)/(x_2-x_1)

We have

f(-9) = 10 → (-9, 10)

f(-1) = -2 → (-1, -2)

Substitute:


m=(-2-10)/(-1-(-9))=(-12)/(8)=-(3)/(2)=-1.5\\\\y-10=-1.5(x-(-9))\\\\y-10=-1.5(x+9)\qquad|\text{use distributive property}\\\\y-10=-1.5x-13.5\qquad|+10\\\\y=-1.5x-3.5

Answer: f(x) = -1.5x - 3.5

User RobotHumans
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