Question

Caucule o valor de x de modo que: 
a)2x+3=15
b)7x-1=13
c)2x-4=3
d)4x+2=18
e)5x-2=7+6
f)10x+1=-4-5

Answer 1

a) $2x+3=15 \to 2x=15-3 \to 2x=12 \to \frac{12}{2} \to x=6$

b) $7x-1=13 \to 7x=13+1 \to 7x=14 \to x= \frac{14}{7} \to x=2$

c) $2x-4=3 \to 2x=3+4 \to 2x=7 \to x= \frac{7}{2} \to x=3,5$

d) $4x+2= 18 \to 4x=18-2 \to 4x=16 \to x= \frac{16}{4} \to x=4$

e) $5x-2=7+6 \to 5x-2=13 \to 5x=13+2 \to 5x=15 \to x= \frac{15}{5}$
$\to x=3$

f)$10x+1=-4-5 \to 10x+1=-9 \to 10x=-9-1 \to 10x=-10$
$\to x= \frac{-10}{10} \to x=-1$