Question

Translate this word problem as a system of equations and then solve using substitution.

The sum of two numbers is 84. One number is three times the other. Find the numbers. @mathstudent55

Answer 1

We start in a similar way to the previous problem, assigning variables to the unknown numbers.
Let one number be x. Let the other number be y.

The sum of the numbers is x + y. We are told the sum is 84, so our first equation is
x + y = 84

Answer 2

wht the answer

Answer 3

Then we are told one number is three times the other. We represent that with:
x = 3y

The system of equations is:
x + y = 84
x = 3y

Answer 4

whats hr answer @mathstudent55

Answer 5

Since the second equation is already solved for x, we just substitute it into the first eqation.
3y + y = 84
4y = 84
y = 21
Now substitute y = 21 into second equation:
x = 3(21)
x = 63
Answer: x = 63, y = 21