Answer:
a = 3 & b = -10
Step-by-step explanation:
(X - 5)^2 + a = X^2 +bX + 28
Solving the left hand side
(X - 5)^2 + a
= (X - 5)(X - 5) + a
= X^2 - 5X - 5X + 25 + a
= X^2 - 10X + 25 + a
Equating the the right hand side
X^2 - 10X + 25 + a = X^2 +bX + 28
: -10X = bX
X = -10 and
25 + a = 28
a = 28 - 25
a = 3
