Question

If x + y = 8 and xy =15/4 , find the values of
(ii) 3(x2 + y2) (iii) 5(x2 + y2) + 4(x - y).
(i) x - y​

Answer 1

Step-by-step explanation:

a.3(x^2+y^2)=3((x+y)^2-2xy)=3*(64-15/2)=113*3/2=339/2=169.5

b.5*113/2+4(√(x+y)^2-4xy)=565/2+4*7=621/2=310.5

c.x-y=7 or -7