Question

if a²+b²=58and a-b=4,then find the value of ab​

Answer 1

Step-by-step explanation:

a^2+b^2=58 a-b=4

a^2+b^2=(a-b)^2+2ab

=>58=(4)^2+2ab

=>58=16+2ab

=>2ab=42

=>ab=21

Answer 2

$\huge\mathcal\green{Answer}$

${a}^{2} + {b}^{2} = 58 \\ a - b = 4 \\ \\ {a}^{2} + {b}^{2} = {(a - b)}^{2} + \: 2ab \\ 58 = {4}^{2} + 2ab \\ 58 = 16 + 2ab \\ 58 - 16 = 2ab \\ 42 = 2ab \\ ab = \frac{42}{2} \\ ab = 21$