What is the best first step for solving the given system using substitution while avoiding fractions - 9x+4y=10 - 9x+3y=3

You don't have to simplify either equation to x = ... or y = ... form in this case, because they both have a 9x term. You can substitute that.

-9x + 4y = 10 = > - 9x = (10-4y)

plug that into the second:

(10-4y) + 3y = 3 = > 10 - y = 3 = > y=7

Solve for x in the first equation. Solve for y in the first equation. Solve for x in the second equation. Solve for y in the second equation.

These are the answers, Which one is it.