Answer
Error 1: Miscalculation when squaring the two numbers
Error 2: Rounding to the nearest thousandths
Correct Answer:
$? \approx 11.4$ in
Work Step by Step
1. Explaining the two errors
Error 1: ($9^{2} \ne 18$) and ($7^{2} \ne 14$)
Nine squared and fourteen squared does not equal to the number written in the step after and therefore is the first calculation mistake that they made.
Error 2: $5.657$ rounded to nearest thousandths
The final answer is NOT rounded to the nearest tenths and is instead rounded to the nearest thousandths. The question specifically asks for the final value to be rounded to the nearest tenths and that request was not made. Therefore this was the second mistake that they made.
2. Correct Answer
$?^{2} = 9^{2} + 7^{2}$
$?^{2} = 81 + 49$
$?^{2} = 130$
$? = \sqrt 130$
$? = 11.401...$
$? \approx 11.4$ in
