Part A:
The error in your friend's work appears in Step 4. They made a mistake when multiplying 110 and 5. Instead of multiplying, they should have added these two numbers together.
Part B:
Step 1: 3(15 - 9)^2 + 2 • 5
Step 2: 3(6)^2 + 2 • 5
Step 3: 3(36) + 2 • 5
Step 4: 108 + 2 • 5
Step 5: 108 + 10
Step 6: 118
Your friend asks you to check their work. You see the expression 3( 15 - 9)^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
Part A: Explain, using complete sentences, in which step and what specifically your friend’s error was.
Part B: Correctly simplify this expression using a similar format - showing work for each step like was done above. Full credit will only be given if work shows Step 1, Step 2, Step 3, etc, as seen above.
1 answer