Question

(25 x)2 - 20 x y - (21 y) 2 + 10 Y Z - (z)2. ..///////(...))means an whole square​

Answer 1

Answer:

$\mathrm{\left(25x\right)^2-20xy-\left(21y\right)^2+10yz-z^2=625x^2-20xy-441y^2+10yz-z^2}$

Step-by-step explanation:

$\mathrm{\left(25x\right)^2-20xy-\left(21y\right)^2+10yz-z^2}$

$\mathrm{Apply\:exponent\:rule:\quad \left(a\cdot \:b\right)^n=a^nb^n}$

$\mathrm{=25^2x^2-20xy-\left(21y\right)^2+10yz-z^2}$

$\mathrm{Apply\:exponent\:rule:\quad \left(a\cdot \:b\right)^n=a^nb^n}$

$\mathrm{=25^2x^2-20xy-21^2y^2+10yz-z^2}$

$\mathrm{=625x^2-20xy-441y^2+10yz-z^2}$