2
1) Let's evaluate 1+x+2=5
1+x +2=5 Adding the numbers on the left side
+3 = 5 S subtract 3 from both sides
x = 5-3
x = 2
2) Hence, the answer is x=2
1+ x +2 = 5
1+ 2+ 2 =5
5 = 5 True
