Your friend asks you to check their work. You see the expression 3(15−9)2 + 2 ⋅5

simplified in the following way:

Original Problem: 3(15−9)2 + 2 ⋅ 5
Step 1: 3(6)2 + 2 ⋅5
Step 2: 3(36)+ 2 ⋅ 5
Step 3: 108 + 2 ⋅ 5
Step 4: 110 ⋅ 5
Step 5: 550

1 answer

The simplified expression is incorrect. The error occurred in Step 4. The expression should not be multiplied by 5, but rather added to it.

Here's the correct simplification:

Step 4: 108 + 2 ⋅ 5 = 108 + 10 = 118

Therefore, the correct simplified expression is 118.