Algebra
posted by Team A on .
need help in solving by substitution. We all have different steps and all arrive at 3 different ordered pairs. please help and show the steps for
7x+6y=15 and 7x+y=27. Thanks

It takes work to find the answers, but it is much easier to check a given answer, namely by backsubstitution. This is especially important in exams where you can check and reassure yourself you have the right answer.
for
7x+6y=15...(1)
7x+y=27...(2)
add (1) and (2) to get
7y=42
Solve for y and substitute y in (1) to get x=3.