Question

1. Find the value of:
(i) a + b when a + b = 9, ab = 20​

Answer 1

Answer:

a+b)²=(a-b)² + 4ab

9 * 9 = (a-b)²+4*20

81 = (a-b)² +80

81 - 80 = (a-b)²

1 = (a-b)²

taking root both the side,

1 = a-b

Marks me brainlist.