Question

if [4x-y] =10 and xy=3 then find 16x2+y2

Answer 1

Given:-

4x-y=10

xy=3

To find:-

16x²+y²

Solution:-

By,squaring both the sides in 4x-y=10,we get-----

(4x-y)²=(10)²

We,know that (a-b)²=a²+b²-2ab

(4x)²+(y)²-2×4x×y=100

16x²+y²-8xy=100

By,putting value of xy in the above equation,we get----

16x²+y²-8×3=100

16x²+y²-24=100

16x²+y²=100+24

16x²+y²=124