Question

3

Rewrite the following equation as a function of x.
21x+3y-45=0
A. f(x)= 7x-15
B. f(x)=-7x-6
C. f(x)=3x+6
D. f(x) = -7x + 15

Answer 1

D. -7x + 15

Explanation:

In order to rewrite the equation as a function of x, we have to isolate y on the left-hand side of the equation:

`(21x+3y-45=0)+45\\(21x+3y=45)-21x\\(3y=-21x+45)/3\\y=-7x+15`