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Write a linear function f with the values f (5) =4 and f (3)= -8

User Vikram Parimi
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1 Answer

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23 votes

Answer:

f(x) = 6x -26

Explanation:

You want a linear function f with the values f(5) = 4 and f(3) = -8.

Constant slope

One way to do this is to make use of the fact that the ratio of rise to run is the same for all point pairs on the line:

(y -y1)/(x -x1) = (y2 -y1)/(x2 -x1)

(y -4)/(x -5) = (-8 -4)/(3 -5) . . . . . . . . . fill in given point values

-2(y -4) = -12(x -5) . . . . . . . . . . . . cross multiply

y -4 = 6(x -5) . . . . . . . . divide by -2

f(x) = 6x -26 . . . . . . add 4 and simplify; desired functional form

Write a linear function f with the values f (5) =4 and f (3)= -8-example-1
User Nerdybeardo
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