Answer: 2x+1
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Work Shown:
(x+2)+(x-1)
x+2+x-1
x+x+2-1
(x+x)+(2-1)
2x+1
In this case, the parenthesis don't really change the expression. So the jump from step 1 to step 2 is merely cosmetic as far as I'm concerned. The like terms x and x add to 2x. It's like saying "one box + one box = two boxes". The other like terms 2 and -1 combine to 1.