The numbers: x, y x·y=-14 x+y=5 ⇒ y=5-x Substitute y in the first equation by y from second one x·(5-x)=-14 5x-x²=-14 -x²+5x+14=0 -x²-2x+7x+14=0 -x(x+2)+7(x+2)=0 (x+2)(-x+7)=0 Product is 0 if one of factors is 0 x+2=0 or -x+7=0 x=-2 or -x=-7 x=-2 or x=7 Now back to the equation y=5-x y=5-(-2) or y=5-7 y=7 or y=-2
