Question

express a2 +25b2 +4 - 5ab - 10b-2a as a a sum of perfect square​

Answer 1

multiply and divide by 2

1/2(2a2+ 50b2 +8-10ab-20b-4a)

= 1/2(a2+25b2-10ab + 25b2+4-20b +a2+4-4a)

=1/2{(a-5b)^2 + (5b-2)^2 + (a-2)^2}

Answer 2

1/2{(a-5b)^2 + (5b-2)^2 + (a-2)^2}