Question

$\large\huge\ { \fcolorbox{blue}{aqua}{\red{If a²+b² = 21 , ab = 2 then find a+b}}}$​​

Answer 1

$\huge \fbox \purple{❥ Answer}$

a²-b²=21

a²+b²=29

a²+b²+a²-b²=21+29

2a²=50

a²=25

a=√25

a=±5

a²-b²=21

25-b²=21

b²=4

b=±5

a²+b²=(a+b)²-2ab

29=±7²-2ab

29=49-2ab

ab=10

so,ab =10

hope helped

Answer 2

Step-by-step explanation:answer=5

Given

${a }^{2} + {b}^{2} = 21$

$ab = 2$

${(a + b)}^{2} = {a}^{2} + {b}^{2} + 2ab \\ \: \: \: \: \: \: \: \: = 21 + 2(2) \\ = 25 \\ a + b = \sqrt{25}$

therefore a+b=5