Hi there!
mistake= step 2..
If you can see, the equation is the opposite so this means that to find the answer, your gonna have to add first.. instead of subtracting..
<em><u>1.Add the terms:</u></em>
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<em><u>2.Simplifly the terms:</u></em>
<em><u /></em><em><u /></em>
<em><u>3.Subtract the terms:</u></em>
<em><u /></em><em><u /></em>
Therefore, the mistake was step 2...