Question

If a + b = 9 and ab = -22, find(1) a - b (ii) a2- b2​

Answer 1

Step-by-step explanation:

Hi,

a + b = 9 ---------(1)

a × b = -22 ---------(2)

From equation (2) , we get

a = -22/b --------(3)

Putting the Value of a in equation (1) , we get

a + b = 9

-22/b + b = 9

-22 + b² = 9b

b² - 9b -22 = 0

b² - 11b + 2b - 22 = 0

b ( b - 11 ) + 2 ( b - 11 ) = 0

( b - 11 ) ( b + 2 ) = 0

( b - 11 ) = 0 , or ( b + 2 ) = 0

b = 11 or b = -2

Taking b = 11

Putting the value of b in equation (1), we get

a + b = 9

a + 11 = 9

a = -2

Now,

a - b = -2 - 11 = -13

And,

(a)² - (b)² = ( a + b ) ( a-b) = 9 × (-13) = -117

Hence,

( a - b ) = -13 and (a)² - (b)² = -117.

Hope it will help you :))

Answer 2

Answer:

Hello dear friend

Step-by-step explanation:

Your answer is there above.......

answered by my cute sister