2x - y = 15
2x + 3y = -21
As you observe both equations (having different slopes), you see that the system is consistent, and it has only one solution.
15xy-2xy-7x+x=13xy-6x
Y=15/(2c+2x)
2xy - 4x plus 8y - 16 equals x plus 4 in parentheses multiplied by 2y minus 4 in parentheses. So, the factors are ( x + 4) and ( 2y - 4) .
2xy=2*30*2=120
x2 + y2 = x2 - 2xy + y2 + 2xy = (x - y)2 + 2xy = 72 + 2*8 = 49 + 16 = 65 You could, instead, solve the two equations for x and y and substitute, but the above method is simpler.
15xy-2xy-7x+x=13xy-6x
It's an hyperbola equation.
Y=15/(2c+2x)
Because 2x+y is addition not multiplication
2xy + 6xy = 8xy
2xy - 4x plus 8y - 16 equals x plus 4 in parentheses multiplied by 2y minus 4 in parentheses. So, the factors are ( x + 4) and ( 2y - 4) .
2xy=2*30*2=120
That equals 2xy + 3y which factors to y(2x + 3)
L = 3x + 2y
What is : 5xy- x2t + 2xy + 3x2t
2xy substitute 3 for y and 5 for x 2(5)(3) = 30
The three terms are: -3xy2, 2xy and -4y3