.2x+3y=8 and xy=-1 find 4x^(2)+9y^(2)
Answers
Answered by
1
Answer:
66
Step-by-step explanation:
4x^(2)+9y^(2)
= (2x)^2 + (3y)^2
= (2x + 3y)^2 - 2xy [a^2 +b^2 = (a+b)^2 -2ab]
= 8*8 - (2 * -1)
= 64+ 2
=66
Similar questions