Question

2. Observe o triângulo a seguir;
2x +20
4x +40
6x +60
Qual é o valor de x neste triângulo?
a3
b5
c7
d9​

Answer 1

$\sf     2x + 4x + 6x + 2 0 + 40 + 60 = 180 \\ \sf     6x + 6x + 20 + 40 + 60 = 180 \\\sf     12x + 20 + 40 + 60 = 180 \\ \sf     12x + 60 + 60 = 180 \\ \sf     12x +120 = 180 \\ \sf     12x = 180 - 120 \\ \sf     12x = 60 \\ \sf     x = \frac{60}{12} \\ {\color{Yellow}\boxed{\sf  x = 5}}$

Att: Nerd1990