You can put this solution on YOUR website! We will call the larger of two numbers L and the smaller of the numbers S.
Three times the larger of two numbers is equal to four times the smaller.
This can be written as
3L=4S
The sum of the numbers is 21.
This can be written as L+S= 21
We can plug the equation L+S =21 into 3L=4S either using L= 21-S or S= 21-L.
Let's try L= 21-S
3L=4S
3(21-S)= 4S
63 -3S = 4S
-3S-4S = -63
-7S = -63
7S = 63
S = 9
If S=9, then 3L=4S
3L= 4(9)
3L= 36
L= 12
Check our work
3L= 4S
3(12) = 4 (9) Yes!