Question

Show that (5x – 2y)2 + 20xy = 25x2 + 4y ?​

Answer 1

(5x – 2y)² + 20xy = 25x² + 4y²

LHS = (5x – 2y)² + 20xy

= 25x² + 4y² - 20xy + 20xy

= 25x² + 4y²

= RHS

LHS = RHS

Hence proved ✓✓

Answer 2

The correct question is as follows;

To Prove:

$(5x - 2y)^{2}$ + $20xy$ = $25x^{2}$ + $4y^{2}$

Proof:

Here, we have to use the simple identity of $(a-b)^{2}$ expansion as follows;

We have,  $(a-b)^{2}$ = $a^{2}-2ab+b^{2}$

Now, just substituting the values of a and b as 5x and 2y respectively, we get;

⇒ LHS = $(5x - 2y)^{2}$ + $20xy$

           = $(5x)^{2} - 2(5x)(2y)+(2y)^{2}$ +  $20xy$

           = $25x^{2} - 20xy + 4y^{2}$ + $20xy$

           = $25x^{2} +4y^{2}$

           = RHS

∵  LHS = RHS

Hence Proved.

#SPJ6