Question

(7m- en ) ² + (7 m+ 8n)​

Answer 1

Step-by-step explanation:

98m2+128n2

Given, (7m−8n)2+(7m+8n)2.

We know, (a−b)2=a2−2ab+b2 

and (a+b)2=a2+2ab+b2.

Then,

(7m−8n)2+(7m+8n)2

=[(7m)2−2(7m)(8n)+(8n)2]+[(7m)2+2(7m)(8n)+(8n)2]

=(49m2−112mn+64n2)+(49m2+112mn+64n2)

=49m2−112mn+64n2+49m2+112mn+64n2

=98m2+128n2.