Question

tell whether the equation X (X + 4) - X square + 3 Y + 5 = 0 is a linear equation in two variables or not

Answer 1

yes ,
$x(x + 4) - x {}^{2} + 3y + 5 = 0 \\ {x}^{2} + 4x - x {}^{2} + 3y + 5 = 0 \\ 4x + 3y + 5 = 0$
ie x&y is two veriable of the equition.