Question

if a + b = 10 and ab = 18 find the. value of a² + b ² answer​

Answer 1

Answer:

$a^{2} +b^{2}=64$

Step-by-step explanation:

a+b=10 ab=18

as you know $(a+b)^{2} =a^{2} +2ab+b^{2}$

a+b=10, raise both sides to the power of 2

It gives us:

$a^{2} +2ab+b^{2} =100$

ab=18, you can replace 18 instead of ab:

$a^{2} +2(18)+b^{2} =100$ now multiply 2 by 18. $a^{2} +36+b^{2} =100$

now -36 both sides:

$a^{2} +b^{2} =64$