If `P=7x^2+5xy-9y^2 ,\ Q=4y^2-3x^2-6x y\ ` and `R=-4x^2+x y+5y^2,\ s how\ t h a t\ P+Q+R=0.`

If P=7x^2+5x y-9y^2,\ Q=4y^2-3x^2-6x y and R=-4x^2+x y+5y^2, show that P+Q+R=0.

Add x^2+y^2+3xy-6 and 2x^2-4y^2-xy+5

Subtract: x^2-3x y+7y^2-2 from 6x y-4x^2-y^2+5

Solve for (x - 1)^(2) and (y + 3)^(2) , 2x^(2) - 5y^(2) - x - 27y - 26 = 3(x + y + 5) and 4x^(2) - 3y^(2) - 2xy + 2x - 32y - 16 = (x - y + 4)^(2) .

Subtract 5x^2 - 4y^2 + 6y - 3 from 7x^2 - 4xy + 8y^2 + 5x - 3y .

Evaluate : 3x^(2) + 5xy - 4y^(2) + x^(2) - 8xy - 5y^(2)

Subtract: 2x^2 -5xy +3y^2+5 from 4x^2+3xy-5y^2+9

Add: (i) x y^2+4x^2y-7x^2y-3x y^2+3\ a n d\ x^2y+x y^2 (ii) 5x^2+7y-6z^2,\ 4y+3x^2,9x^2+2z^2-9y\ a n d\ 2y-2x^2

If P_(1), P_(2), P_(3) are the perimeters of the three circles, S_(1) : x^(2) + y^(2) + 8x - 6y = 0 S_(2) : 4x^(2) + 4y^(2) -4x - 12y - 186 = 0 and S_(3) : x^(2) + y^(2) -6x + 6y - 9 = 0 respectively, then the relation amongst P_(1), P_(2) and P_(3) is .............

In the algebraic expression 5x^2y+7x y^2-3x y-4y x^2, we have 5x^2y and -4y x^2 as like terms, whereas 7x y^2 and -3x y are unlike terms.