Question

Please help me with 5th question

Answer 1

Given a + b = 7 and ab = 10.

On squaring both sides, we get

= > (a + b)^2 = (7)^2

= > a^2 + b^2 + 2ab = 49

= > a^2 + b^2 + 2(10) = 49

= > a^2 + b^2 + 20 = 49

= > a^2 + b^2 = 49 - 20

= > a^2 + b^2 = 29

Now,

We know that:

= > a^2 + b^2 = (a - b)^2 + 2ab

= > 29 = (a - b)^2 + 2(10)

= > 29 = (a - b)^2 + 20

= > 29 - 20 = (a - b)^2

= > 9 = (a - b)^2

= > a - b = 3.


Therefore the value of a - b = 3.


Hope this helps!

Answer 2

Hi,

Please see the attached file !


Thanks