Question

$217\times 217+183\times 183=$?

• A. $79698$
• B. $80578$
• C. $80698$
• D. $81268$

Answer 1

The correct option is B $80578$

${\left(217\right)}^2+{\left(183\right)}^2={(200+17)}^2+{(200-17)}^2$
$=2\times [{\left(200\right)}^2+{\left(17\right)}^2]$ [Ref: ${(a+b)}^2+{(a-b)}^2=2(a^2+b^2)$]
$=2[40000+289]$
$=2\times 40289$
$=80578$