Question

Calcule o valor de x no trapézio isósceles a seguir.​

Answer 1

$360^o = 2(2a+40^o) + 2(2a+80^o)\\360^o = 4a+80^o + 4a+160^o\\360^o = 8a+80^o+160^o\\360^o = 8a+240^o\\8a = 360^o - 240^o\\8a = 120^o\\a = 15^o\\\\x = 180^o - (2a + 80^o)\\x = 180^o - (2\mbox{ } . \mbox{ }15^o + 80^o)\\x = 180^o - (30^o + 80^o)\\x = 180^o - 110^o\\x = 70^0$