Question

alguém pode me ajudar
a) 2x + 8 = 3 − 4
b) 3x − 9 = 1x + 3
c) 2 + 8 − 7 = 3x d) 4x + 7 = 8 + 3x
e) x + 7 − 8 = 5
f) 5 + 13 + 5x = 3 + 4x g) 1x + 3x = 16
h) 4x + 34 = 15 − 2x + 3
i) 2x + 40 − 25 = 15

Answer 1

Resposta:

$2x + 8 = 3 - 4\\\\2x+8=-1\\\\2x+8-8=-1-8\\\\2x=-9\\\\\frac{2x}{2}=\frac{-9}{2}\\\\x=-\frac{9}{2}\\\\\\3x -9= x + 3\\\\3x -9 + 9= x + 3 + 9\\\\3x = x+12\\\\3x -x= x+12 -x\\\\2x = 12\\\\2x/2 = 12/2\\\\x =6$

$2 + 8 - 7 = 3x \\\\3x=2+8-7\\\\3x=3\\\\\frac{3x}{3}=\frac{3}{3}\\\\x=1$

$4x + 7 = 8 + 3x\\\\4x+7-7=8+3x-7\\\\4x=3x+1\\\\4x-3x=3x+1-3x\\\\x=1$

$x + 7 - 8 = 5\\\\x-1=5\\\\x-1+1=5+1\\\\x=6$

$5+13+5x=3+4x\\\\5x+18=3+4x\\\\5x+18-18=3+4x-18\\\\5x=4x-15\\\\5x-4x=4x-15-4x\\\\x=-15$

$1x + 3x = 16\\\\4x=16\\\\\frac{4x}{4}=\frac{16}{4}\\\\x=4$

$4x + 34 = 15 - 2x + 3\\\\4x+34=-2x+15+3\\\\4x+34=-2x+18\\\\4x+34-34=-2x+18-34\\\\4x=-2x-16\\\\4x+2x=-2x-16+2x\\\\6x=-16\\\\\frac{6x}{6}=\frac{-16}{6}\\\\x=-\frac{8}{3}$

$2x+40-25=15\\\\2x+15=15\\\\2x+15-15=15-15\\\\2x=0\\\\\frac{2x}{2}=\frac{0}{2}\\\\x=0$