Question

dada a função f(x)=2x+3 , determine os valores de x para que:
a) f(x)=1

b) f(x)=0

c) f(x)=⅓​

Answer 1

a)

$1 = 2x + 3 \\ \\ 2x + 3 = 1 \\ 2x = 1 - 3 \\ 2x = - 2 \\ \\ \frac{2x}{2} = \frac{ -2 }{2} \\ \\ x = - 1$

b)

$0 = 2x + 3 \\ \\ 2x + 3 = 0 \\ 2x = - 3 \\ \\ \frac{2x}{2} = \frac{ - 3}{2} \\ \\ x = - 1.5$

c)

$2x + 3 = \frac{1}{3} \\ \\ 2x = \frac{1}{3} - \frac{9}{3} \\ \\ 2x = - \frac{8}{3} \\ \\ (2x) \times \frac{1}{2} = ( - \frac{8}{3} ) \times \frac{1}{2 } \\ \\ x = - \frac{8}{6} \\ \\ x = - \frac{4}{3}$