Further applications of linear equations

Question

The numbers on two consecutively numbered gym lockers have the sum of 141 what are the locker numbers

Answer 1

You can create a system of equations. Let x = the first number and y = the second number.

Since the numbers are consecutive, the difference would be 1. Then, the first equation in the system is

y - x = 1

Next, the two values have the sum of 141, which means the next equation in the system is

y + x = 141

To solve the system of equation, you can use the substitution, graphing or elimination method. For this example, I'll use elimination .

y - x = 1

y + x = 141 The x's are the same with different signs so they will eliminate when you add the two equations together.

2y = 142

y = 71 Here's I divided both sides by 2.

Since y was named the 2nd number, the first number has to be 70.

Check you answer.....70 and 71 are consecutive and the sum of the two is 141.