Question

If a+b=5 and a²+b²=13, then ab is equal to

Answer 1

[tex]\mathfrak{\huge{Answer:-}} \\ \bold{a + b = 5} \\ Squaring \: on \: both \: the \: sides \\ {(a + b)}^{2} = {(5)}^{2} \\ {a}^{2} + {b}^{2} + 2ab = 25 \\ 15 + 2ab = 25 \\ 2ab = 25 - 15 \\ 2ab = 10 \\ab = \frac{10}{2} \\ \large{\boxed{\boxed{\bold{ ab = 5}}}}[/tex]