Resposta :
Resposta:
x = 20
Explicação passo-a-passo:
2x - 10 + 7x + 10= 180
2x + 7x = 180 + 10 - 10
9x = 180
x = 180/9
x = 20
[tex]\Large\boxed{\begin{array}{l}\sf 2x-\diagdown\!\!\!\!\!\!10+7x+\diagdown\!\!\!\!\!\!\!10=180\\\sf 9x=180\\\sf x=\dfrac{180}{9}\\\sf x=20\end{array}}[/tex]