Question

calcule os valores de X utilizando a ideia de operações inversas

a) 5X+10=25

b) 5X+2X=70

c) 6X=78

d) 8X=96

e) X•X=81 ​

Answer 1

$a)5x + 10 = 25\\5x = 25 - 10\\5x = 15\\x = \frac{15}{5}\\ x = 3\\\\b)5x + 2x = 70\\7x = 70\\x = \frac{70}{7}\\ x = 10\\\\c)6x = 78\\x = \frac{78}{6}\\x=13\\\\d) 8x = 96\\x = \frac{96}{8}\\ x =12\\\\e) x * x = 81\\x^2 = 81\\x = \sqrt{81}\\ x = 9$