Question

1. Encontre o valor de x:

Answer 1

Resposta:

- Todas as figuras dessa questão possuem a soma dos ângulos internos igual a 360°.

$a) 110+80+60+x=360$

  $x=360-110-80-60\\x=250-80-60\\x=170-60\\x=110$

→Substituição←

$110+80+60+x\\110+80+60+110\\190+60+110\\250+110\\360$

==============================================

$b) x+5x+4x+2x=360$

  $12x=360$

     $x=360:12\\x=30$

→Substituição←

$x+5x+4x+2x\\30+5.30+4.30+2.30\\30+150+120+60\\180+120+60\\300+60\\360$

==============================================

$c)90+80+120+x=360$

  $x=360-90-80-120\\x=270-80-120\\x=190-120\\x=70$

→Substituição←

$90+80+120+x\\90+80+120+70\\170+120+70\\290+70\\360$

==============================================

$d)x+5x+x+5x=360$

  $12x=360$

     $x=360:12\\x=30$

→Substituição←

$x+5x+x+5x\\30+5.30+30+5.30\\30+150+30+150\\180+30+150\\210+150\\360$