if 2x+6y=60 and xy=1, find x2+ 9y2 - Maths - Algebraic Expressions and Identities

Question

if 2x+6y=60 and xy=1, find x2+ 9y2

K.vignesh · Accepted Answer

2x+6y=60
x+3y=30(dividing both sides by 2)
(x+3y)2=302(squaring both sides)
x2+9y2+6yx=900[
(a+b)2=a2+b2+2ab) constitute that
here ]
x2+9y2=900-6*1(x*y=1)
x2+9y2=894
hope it helps