Symbol
Problem
The coordinate axes are rotated through an angle $θ$ about the origin in $3$ sense.If the equation $2x^{2}+3xy-6x+2y-4=0$ changes $10$ $5$ $=$ $+$ $a+b$ $ax^{2}+2hxy+by^{2}+2gx+21y+c=0$ is equal to $1\right)$ $3cosθ-3sin$ $θ$ $2\right)$ $3cosθ+2sin$ $0$ $3\right)$ $4\right)$ $2$