If `x*y=x^2+y^2-x y` , then the value of `9*11` is (a) 93 (b) 103 (c) 113 (d) 121

If x+y=2a then the value of (a)/(x-a)+(a)/(y-a) is (a) 2 (b) 0(c)-1 (d) 1

If x+y=15 a n d x y=56 , then what is the value of x^2+y^2? (a) 110 (b) 113 (c) 121 (d) Cannot be determined (e) None of these

If x-y=9 and xy=16 then the value of x^(2)+y^(2)

If 2x+3y=31,backslash backslash y-z=4 and x+2z=11, then what is the value of x+y+z?( a )12 (b) 13 (c) 15 (d) 16

If x+y=15 and xy=56, then what is the value of x^(2)+y^(2)?( a )110( b) 113(c)121 (d) Cannot be determined (e) None of these

If x-y=1 and x^(2)+y^(2)=41, then the value of x+y will be (a)5 or 4(b)-5 or -4 (c) +-9(d)+-1

If parabolas y^(2)=lambda x and 25[(x-3)^(2)+(y+2)^(2)]=(3x-4y-2)^(2) are equal,then the value of lambda is 9(b)3(c)7 (d) 6

If 2x+y=17;y+2z=15 and x+y=9 then what is the value of 4x+3y+z?(a)41 (b) 43(c)45 (d) 55 (e) None of these

If 2x+y=15,1backslash2y+z=25 and 2z+x=26, what is the value of z?( a )4 (b) 7( c) 9(d)11