The sum 8

The sum of the two numbers is 21. If three times the smaller numbers are two less than twice the larger number, find the two numbers.

Correct answer:

a =  8
b =  13

Step-by-step explanation:


a+b=21
3a = 2b-2

a+b=21
3·a = 2·b-2

a+b = 21
3a-2b = -2

Pivot: Row 1 ↔ Row 2
3a-2b = -2
a+b = 21

Row 2 - 1/3 · Row 1 → Row 2
3a-2b = -2
1.67b = 21.67


b = 21.66666667/1.66666667 = 13
a = -2+2b/3 = -2+2 · 13/3 = 8

a = 8
b = 13

Our linear equations calculator calculates it.



Did you find an error or inaccuracy? Feel free to write us. Thank you!







Tips for related online calculators
Do you have a system of equations and looking for calculator system of linear equations?

You need to know the following knowledge to solve this word math problem:

Related math problems and questions: