Question

Atividade de matemática
1) Resolva as equações
a)x+7=15
b)2x+6=10
c)3y-7=21
d)-6+4x=12
h)+4-7m=6
I)5x-10=10
J)6a+3=3
K)+3+8p=21
e)4m+6=18
f))+3-6y=20
g)+7-2x=24
alguém plsss​

Answer 1

$a)x + 7 = 15 \\ x = 15 - 7 \\ x = 8$

$b)2x + 6 = 10 \\ 2x = 10 - 6 \\ 2x = 4 \\ x = \frac{4}{2} \\ x = 2$

$c)3y - 7 = 21 \\ 3y = 21 + 7 \\ 3y = 28 \\ y = \frac{28}{3} \\ x = 4$

$d) - 6 + 4x = 12 \\ 4x = 12 + 6 \\ 4x = 18 \\ x = \frac{18}{4} \\ x = 4.5$

$e)4m + 6 = 18 \\ 4m = 18 - 6 \\ 4m = 12 \\ m = \frac{12}{4} \\ m = 3$

$f)3 - 6y = 20 \\ - 6y = 20 - 3 \\ - 6y = 17 \\ - y = \frac{17}{6} \\ - y = 2.83 \: \: \times ( - 1) \\ y = - 2.83$

$g)7 - 2y = 24 \\ - 2y = 24 - 7 \\ - 2y = 17 \\ - y = \frac{17}{2} \\ - y = 8.5 \times ( - 1) \\ y = - 8.5$

$h)4 - 7m = 6 \\ - 7m = 6 - 4 \\ - 7m = 2 \\ - m = \frac{2}{7} \\ - m = 0.28 \times ( - 1) \\ m = - 0.28$

$i)5x - 10 = 10 \\ 5x = 10 + 10 \\ 5x = 20 \\ x = \frac{20}{5} \\ x = 4$

$j)6a + 3 = 3 \\ 6a = 3 - 3 \\ 6a = 0 \\ a = \frac{0}{6} \\ a = 0$

$k)3 + 8p = 21 \\ 8p = 21 - 3 \\ 8p = 18 \\ p = \frac{18}{8} \\ p = 2.25$