Respuesta :
5(9x+5y=28)-9(5x+9y=56)=0
(45x+25y=140)-(45x+81y=504)=0
45x+25y-45x-81y=-364
-56y=-364
y=6.5, now use either original equation to solve for x...
9x+5(6.5)=28
9x+32.5=28
9x=-4.5
x=-0.5
So the single solution (x,y) is (-0.5, 6.5)
(45x+25y=140)-(45x+81y=504)=0
45x+25y-45x-81y=-364
-56y=-364
y=6.5, now use either original equation to solve for x...
9x+5(6.5)=28
9x+32.5=28
9x=-4.5
x=-0.5
So the single solution (x,y) is (-0.5, 6.5)
The solution set would be (-0.5,6.5). Make sure to put the negative first since it is the smaller number.