Question

Hallar el valor de X y verificar :
A. 5X +6=21
B -2X+8=-2
C. 2X+4=6
D.-X + 1=-8

Answer 1

a)
$5x + 6 = 21 \\ 5x = 21 - 6 \\ x = 3 \\ verificar \\ 5(3) + 6 = 21 \\ 15 + 6 = 21 \\ es \: correcto$
b)
$- 2x + 8 = - 2 \\ - 2x = - 2 - 8 \\ - 2x = - 10 \\ 10 = 2x \\ 5 = x \\ verificar \\ - 2(5) + 8 = - 2 \\ - 10 + 8 = - 2 \\ es correcto$
c)
$2x + 4 = 6 \\ 2x = 6 - 4 \\ 2x = 2 \\ x = 1 \\ verificar \\ 2(1) + 4 = 6 \\ 2 + 4 = 6 \\ es \: correcto$
d)
$- x + 1 = - 8 \\ - x = - 8 - 1 \\ - x = - 9 \\ 9 = x \\ verificar \\ - 9 + 1 = - 8 \\ es \: correcto$