Question

Let f(x)=7x+4 find each value
A. f(x) when x = -8
B. f(3)
C. x when f(x) = 67

Answer 1

f(x)=7x+4

When x=-8

f(-8)=7·(-8)+4=-56+4=-52

When x=3

f(3)=7·3+4=21+4=25

When f(x)=67, then :

7x+4=67

7x=63

x=9