what’s the error? and how do you correct it?

Answer:
The mistake is that C is the hypotenuse so the error is the plugging in of C.
Another mistake is the subtraction 64-36 is not 25.
Step-by-step explanation:
Answer:
The mistake is that they switched the value of b with c. They said that c=8, when we actually don't know the value of c. They should have had a second step that looks like this: 6^2+8^2=c^2
You fix this mistake by correcting the values of b and c: 6^2+8^2=c^2
Hope this helps :)