Question 634449
y^2 - 18y + 81 = 25
subtract 25 from both sides and solve it as a quadratic equation
y^2 - 18y + 81 - 25 = 0
y^2 - 18y + 56 = 0
You can use the quadratic formula, but this will factor to
(y-4)(y-14) = 0
Two solutions which are integers
y = 4
and
y = 14