Question

Circle the step the error has occurred. Explain why it is an error.

Given: 2(10 – 13x) = -34x + 60

Step 1: Distribute 20 – 26x = -34x + 60
Step 2: Addition property of Equality -26x = -34x + 80
Step 3: Addition property of Equality 8x = 80
Step 4: Division Property of Equality x = 10

Answer 1

The error lies in step 2

You subtract 20. To 60, not add

Answer 2

Step 2 has an error

Explanation:

Given equation,

2(10 - 13x) = -34x + 60

By distributive property,

20 - 26x = -34x + 60

Now, we need to isolate x on the left side of the equation,

For this we need to eliminate constant term from the left side,

20 will be eliminated by subtracting 20 from both sides ( subtraction property of equality )

I.e. Step 2 has an error,

We need to use subtraction property of equality instead of using addition property of Equality,

Note : The correct steps would be,

Step 2 : 20 - 26x = -34x + 60 ( Subtraction property of equality )

Step 3 : 8x = 40 ( addition property of Equality )

Step 4 : x = 5 ( Division Property of Equality )