system of equations problem

Question

how many solutions does the following system of linear equations have??

14x - 7y = 21

2x - y = 3

Answer 1

Another way to solve this equation is through replacement.

Since y is alone for the second equation [2x-y=3] Make it into a y='s equation [y=2x-3]

Replacing y in the first equation 14x-7(2x-3)=21

the equation says 21=21

therefore any number can replace x and there are infinite solutions

Answer 2

Hi Lily.

If you try to solve this by Elimination, one option would be to multiply all of the terms in the second equation by 7. If you do that, you can see that BOTH lines are 14x-7y=21.

If the lines are identical, that means that every point is a solution, so the answer is INFINITE SOLUTIONS.

Hope this helps.