Question

find the value of the following algebraic expression ( x + y )² - ( x - y)² if the x = 1/2 and y = -2​

Answer 1

Expression :

$(x + y)^{2} - (x - y)^{2} \\ the \: value\: of \: x = \frac{1}{2} \: and \: y = - 2$

$on \: putting \: the \: values \: in \: the \\ \: expression$

$( \frac{1}{2} + ( - 2))^{2} - ( \frac{1}{2} - ( - 2))^{2}$

$( \frac{1 - 4}{ 2})^{2} - ( \frac{1 + 4}{2})^{2}$

$(\frac{ - 3}{2} )^{2} - ( \frac{5}{2} )^{2}$

$= \frac{9}{4} - \frac{25}{4} \\ = \frac{9 - 25}{4} \\ = \frac{ - 16}{4}$

$- 4 \\ \: will \: be \: the \: answer$