Question

Simplify: $(z+5{)}^2$

• A. $(z+5{)}^2=z^2+10z+25$
• B. $(z+5{)}^2=z^2+5z+25$
• C. $(z+5{)}^2=z^2+15$
• D. $(z+5{)}^2=z^2-25$

Answer 1

The correct option is A $(z+5{)}^2=z^2+10z+25$

$(z+5{)}^2=z^2+25$
$L.H.S=(z+5{)}^2$
$=z^2+5^2+2\left(z\right)\left(5\right)$
$=z^2+25+10z\ne R.H.S$
The correct statement is $(z+5{)}^2=z^2+25+10z$