Question

If f(x) is a linear function and given f(3)=−3 and f(8)=1, determine the linear function. a.) What is the slope? (Be sure to leave your answer in reduced fraction form.) b.) What is the y-intercept? (Be sure to leave your answer in reduced fraction form.) c.) What is f(x)? f(x)=

Answer 1

slope is 4/5

y intercept is -27/5

f(x) = 4/5x -27/5

Explanation:

The slope is

f(8) - f(3)

----------------

8-3

1 - -3

------------

8-3

1+3

------------

5

4/5

We can use the slope intercept form to find the y intercept

y = mx+b where m is the slope and b is the y intercept

y = 4/5x +b

Using the point (8,1)

1 = 4/5(8)+b

1 = 32/5 +b

Subtract 32/5 from each side

5/5-32/5 = b

-27/5 = b

y = 4/5x -27/5

f(x) = 4/5x -27/5