A student is converting a quadratic from vertex form to standard form, but there is a mistake. Identify the step that contains the mistake and the correction.
STEP 1 y=2(x-5)^2 -1 -----correct
STEP 2 y=2(x^2+25)-1 ------this could be incorrect
STEP 3 y=2x^2-50-1 ------this could also be incorrect
STEP 4 y=2x^2-51 -----correct
CORRECTIONS BELOW...
a. step 2 y=2(x^2-10)-1
b. step 2 y=2(x^2-10x+25)-1
c. step 3 y=2x^2-25-1
d. step 4 y=2x^2-49
PLEASE HELP ME!!!!!!!!!!!!!!!!!