Question

solve
$(3x - 5y) ^{2}$
and verify the answer for
$x = 4$
and
$y = 12$
.
​

Answer 1

$\underline{ \underline{ \mathfrak{Answer}}} \implies \: \\ \implies 2304 \\ \\ \underline{\underline{\mathfrak{Explanation}}} \implies \:$

According to the question:-

$\implies \: {(3x - 5y)}^{2} \\ \\ using \: identity \: \\ \star \: {(a - b)}^{2} = {a}^{2} + {b}^{2} - 2b \\ \\ hence \\ \\ \implies \: 9 {x}^{2} + 25 {y}^{2} - 30xy$

According to the question:-

Putting the given values -

$\implies \: 9 \times 16 + 25 \times 144 - 30 \times 4 \times 12 \\ \\ \implies \: 144 + 3600 - 1440 \\ \\ \implies \:\boxed{ 2304} \\ \\ for \: verification \: \\ \implies \: {(3 \times 4 - 5 \times 12)}^{2} \\ \\ \implies \: {(12 - 60)}^{2} \\ \\ \implies \: {(48)}^{2} = 2304 \\ \\ this \: is \: the \: required \: solution.$

Answer 2

Answer:

Given

X = 4

Y = 12

( 3x - 5y )²

( 3.4 - 5.12 )²

( 12 - 30 )²

( -48 ) ²

2,304

.........OR........

By formula

(3x - 5y)² = 3x² + 5y² - 2.3x.5y

(3.4 - 5.12)² = (3.4)² + (5.12)² - 2.3.4.5.12

=====> 9.16 + 25.144 - 2.12.60

=====> 144 + 3600 - 2.720

====> 3744 - 1440

====> 2,304

Verification :-

( 3x - 5y )²

( 3.4 - 5.12 )²

( 12 - 60 )²

( -48 )²

2,304