Question

Given f(x)=10-2x, find f(7)

Answer 1

f(7)=10-2(7)

f(7)=10-14

f(7)= -4

Answer 2

f
$f(x) = 10 - 2x \\ 7(x) = 10 - 2x \\ 7x = 10 - 2x \\ 7x + 2x = 10 \\ 9x = 10 \\ x = 10 \div 9 \\ x = 1.11.....$
hope it helps....