Answer:
X=32 and Y=12
The two numbers are 32 and 12
Step-by-step explanation:
Let the number be represented by X and Y
X = 20 + Y-------- equation 1
3X - Y = 84------- equation 2
solving the equation by substitution;
we substitute equation 1 into equation 2, we have;
3(20+Y)-Y = 84
expanding the bracket;
60 + 3Y - Y = 84
60 + 2Y = 84
2Y = 84 - 60
2Y = 24
divide both sides by 2;
2Y/2 = 24/2
Y = 12
from equation 1, we can find X by using the value of Y;
X = 20 + Y
X = 20 + 12
X = 32
PROOF:
using equation 2;
[3*32]-12=84
96-12=84
84=84
