Question

if x+y=8 and xy=15/4 find the value of
I) x-y
ii)3(X*2+y*2)
iii)5(X*2+y*2)+4(x-y)​

Answer 1

Step-by-step explanation:

$1) \: ( {x}- {y})^{2} = (x + y) ^{2} - 4xy \\ = (8) ^{2} - 4 \times \frac{15}{4} \\ = 64 - 15 \\ = 49$