375 a system of equations is shown below.
equation a: 5x + 9y = 12
equation b: 4x - 3y = 8
which method eliminates one of the variables?
1) multiply equation a by and add the result
to equation b.
2) multiply equation b by 3 and add the result to
equation a.
3) multiply equation a by 2 and equation b by -6
and add the results together.
multiply equation b by 5 and equation a by 4
and add the results together.