Answer:
Step-by-step explanation:
let the numbers be x and y,then
x+y=18
x=18-y
also xy=-63
(18-y)y=-63
18y-y²=-63
y²-18y-63=0
y²-21y+3y-63=0
y(y-21)+3(y-21)=0
(y-21)(y+3)=0
y=21,-3
when y=21
x=18-21=-3
when y=-3
x=18-(-3)=18+3=21
so numbers are -3 and 21.
