Question

Find the values of the following
expressions.
(i) x2 + y2 if x + y = 7 and xy = 10
(ii) x-y if x + y = 11 and xy = 18
(iii) x + y if x - y = 2V3 and xy = 1
(iv) x2 + y2 if x + y = 8 and xy = 2​

Answer 1

Answer: 1. 29

2. Under root 69

Step-by-step explanation. 1. (X+y)^2= x^2 +y^2 +2xy

On putting the values we get x^2 + y^2= 29

2. We can get x^2 +y^2 from the formula ( x +y)^2= x^2 +y^2 +2xy

Then from formula (X-y)^2= x^2 +y^2 -2xy

We get x-y= under root 69

Similarly you can try other two question