X ^ 2 + 4Y ^ 2 + 4x-4y + 5 = 0, what is the value of 4x-3y?

X ^ 2 + 4Y ^ 2 + 4x-4y + 5 = 0, what is the value of 4x-3y?


simple form
=x²+4x+4+4y²-4y+1
=(x-2)²+(2y-1)²
=0.
So x = 2, y = 1 / 2
4x-3y=8-3/2=13/2.



Known: X-Y / x + y = 4, find the value of X-Y / 2 (x + y) - 4x + 4Y / X-Y


(x-y)/(x+y)=4
So (x + y) / (X-Y) = 1 / 4
(x-y)/[2(x+y)]-(4x+4y)/(x-y)
=(1/2)*[(x-y)/(x+y)]-4[(x+y)/(x-y)]
=(1/2)*4-4*(1/4)
=1



Solve the equations: 4x + y = 9; 3x + 4Y = 10


4x+y=9 (1)
3x+4y=10 (2)
(1) X 4 - (2)
16x-3x=36-10
13x=26
Substituting x = 2 into (1)
y=1