Question

8. If a - b = 09 and ab = 0-36, find :
-
(1) a+b
(ii) a² - 6²​

Answer 1

$a - b = 9 \\ ab = 36 \\ 1. \: \: \: a + b = \sqrt{( {a - b)}^{2} + 4ab } \\ = \sqrt{ {9}^{2} + 4 \times 36} \\ = \sqrt{81 + 144} \\ = \sqrt{225} \\ = 15$