Answer: 13&7
Step-by-step explanation:
The sum of two numbers x&y is 20
Product of the 2numbers xy is 51
X+y=20......equation 1
XY=51.........equation 2
X=20-y.......equation 3
Substitute for x inequation 3 into equation 2
So we have;
(20-y)y=51
Open the bracket
20y-y^2=51
Collect like terms,so we have
Y2-20y+51=0
Factorise
Factors of 51 is 13&7
So -13-7=-20 &-13×-7=51
Substitute
Y2-13y-7y+51=0
Y(y-13)-7(y-13)=0
(Y-7)(y-13)=0
Y-7=0
Y=7 or
Y-13=0
Y=13
Y=13 or 7
Substitute for y in equation 1
X+y=20
X+7=20
X=20-7
X=13 or
X+13=20
X=20-13
X=7
Therefore, X &Y = 13 &7
