#### Question

Show that (9p - 5q)^{2} + 180pq = (9p + 5q)^{2}

#### Solution

L.H.S = (9p − 5q)^{2} + 180pq

= (9p)^{2} − 2(9p)(5q) + (5q)^{2} − 180pq

= 81p^{2} − 90pq + 25q^{2} + 180pq

= 81p^{2} + 90pq + 25q^{2}

R.H.S = (9p + 5q)^{2}

= (9p)^{2} + 2(9p)(5q) + (5q)^{2}

= 81p^{2} + 90pq + 25q^{2}

L.H.S = R.H.S

Is there an error in this question or solution?

Solution Show that (9p - 5q)Square2 + 180pq = (9p + 5q)Square2 Concept: Concept of Identity.