Explicação passo-a-passo:
(x−1)
2
⇒x
−2∗(x)(1)+(1)
=x
−2x+1
3
−3∗(x)
∗(1)+3∗x∗(1)
−(1)
−3x
+3x−1
(x
−2x+1)+(x
+3x−1)=x
−2x
+x
∴x