
Angela C. answered 04/10/19
Experienced Math Tutor & Teaching Assistant
For this problem, we need to form two algebraic equations in order to have a system of equations. The first step is to assign variables to the two numbers we need to solve for. Let's call the:
1st number = x
2nd number = y
The problem states that the 2nd number is 6 less than 3 times the first number. From this, we get our first algebraic equation:
y = 3x - 6
The problem also states that the sum of these two numbers is 26. From this, we get our second algebraic equation:
x + y = 26
Our system of equations is:
I) y = 3x - 6
II) x + y = 26
We can find out what the 1st number is by using the substitution method. Substitute the first equation into the second equation:
x + y = 26
x + (3x - 6) = 26 Substitute.
4x - 6 = 26 Combine like terms.
4x = 32 Add 6 to both sides.
x = 8 Divide both sides by 4.
The 1st number is 8.
Next, we can find out what the 2nd number is by substituting 8 into either the first or second algebraic equation. You can choose either one as they will both give the same correct answer. Let's choose the first equation:
y = 3x - 6
y = 3(8) - 6 Substitute.
y = 24 - 6 Multiply.
y = 18 Combine like terms.
The 2nd number is 18.
Answer:
1st number: 8
2nd number: 18