Question

urgente
resolva as equações;
a) 2x=-8
b) 2x+9=21
c) 3x+7=10
d)y+5y=10-5y
e) 7x-4=4x+11

Answer 1

$a) 2x=-8\to x= \frac{-8}{2} \to x=-4\\\\\\\\ b) 2x+9=21\to 2x=21-9\to 2x=12\to x= \frac{12}{2} \to x=6\\\\\\\\ c) 3x+7=10\to 3x=10-7\to 3x=3\to x= \frac{3}{3} \to x=1\\\\\\\\d)y+5y=10-5y\to y+5y+5y=10\to 11y=10\to y= \frac{10}{11} \\\\\\\\ e) 7x-4=4x+11\to 7x-4x=11+4\to 3x=15\to x= \frac{15}{3} \to x=5$

Answer 2

a) 2x = -8
x = -8 / 2
x = -4

b) 2x + 9 = 21
2x = 21 - 9
2x = 12
x = 12 / 2
x = 6

c) 3x + 7 = 10
3x = 10 - 7
3x = 3
x = 3 / 3
x = 1

d) y + 5y = 10 - 5y
y + 5y + 5y = 10
11y = 10
y = 10 / 11 

e) 7x - 4 = 4x + 11
7x - 4x = 11 + 4
3x = 11 + 4
3x = 15
x = 15 / 3
x = 5