Solve the system by substitution

Question

{-4.5x-2y=-12.5
3:25x-y=-0.75}

Answer 1

I would first of all eliminate those decimals

-4.5x-2y=-12.5
times 2 ------> -9x - 4y = -25 or 9x + 4y = 25

3.25x-y=-0.75
times 4 -------> 13x - 4y = 3

now just add them and things will work out

Answer 2

that last equation should have been

13x - 4y = -3