The calculator came up with this -23.399156493247038795316239455591
Using the Pythagorean theorem:
Hypotenuse = sqrt( 20^2 + 15^2)
Hypotenuse = sqrt( 400 + 225)
Hypotenuse = sqrt(625)
Hypotenuse = 25
Answer: 25 inches
-4+x=9.5
x=13.5
The student might have subtracted 9.5-4, which results in the answer 5.5. The correct answer is 13.5.
