Question

If $x=30\%$ of 30 and $y=x^2+4x+7$,
then y = ___.

• A. 142
• B. 134
• C. 143
• D. 124

Answer 1

The correct option is D 124

$x=30\%\text{of}30=\frac{30}{100}\times 30=9$

Substituting, $x=9$ in $y=x^2+4x+7$, we get

$y=(9{)}^2+4(9)+7=124$

$\therefore$ $y=124$