Question

Calcule o zero de cada função

A) f(×)= -5x+4
B) f(x)=4x - 20
C)f(x)= 1/3x + 120
D) f(x)=x+11

Answer 1

a) f(x) = -5x + 4

-5x + 4 = 0

-5x = -4 ×(-1)

5x = 4

x = 4/5

b) f(x) = 4x - 20

4x - 20 = 0

4x = 20

x = 20/4

x = 5

c)

$\displaystyle \mathsf{f(x) = \frac{1}{3}x + 120} \\ \displaystyle \mathsf{ \frac{1}{3}x + 120 = 0}\\ \displaystyle \mathsf{ \frac{1}{3}x = - 120 } \\ \displaystyle \mathsf{x = - 360}$

d) f(x) = x + 11

x + 11 = 0

x = -11