Question

determine o valor de a no triângulo abaixo​

Answer 1

$\sf 60 {}^{ \circ} + 40 {}^{ \circ} + \alpha = 180 {}^{ \circ} \\ \\ \\ \sf 100 {}^{ \circ} + \alpha = 180 {}^{ \circ} \\ \\ \\ \sf \alpha = 180 {}^{ \circ} - 10 0{}^{ \circ} \\ \\ \\ \sf {\color{red}\alpha = 80 {}^{ \circ} }$

Att: Nerd1990