Question

Write a linear function with f with f (5) = -1 and f (0) = -5

Answer 1

5y = 4x-25

Explanation:

Let f(x) be regarded as y

So we have two points

(5,-1) and (0,-5)

We start by finding the slope of the line connecting the two points

m = y2-y1/x2-x1

m = -5+1/0-5 = -4/-5 = 4/5

The general equation of a straight line is;

y = mx + b

where m

is slope and b is the y-intercept

we already have the slope as 4/5

So;

y = 4x/5 + b

To get b, substitute one of the points

Let us use (0,-5)

-5 = 4(0)/5 + b

so b = -5

The equation is;

y = 4x/5 - 5

Multiply through by 5

5y = 4x - 25