What's -45=10+5y equal

Can someone me with this graph problem by the way i need to know the answers by today since this assignment is due ! !

If wxyz is a square, which statements must be true? plz < 3

Isabelle is mixing red and blue paint to make purple paint she adds 3/10 of a fluid ounce of red to 12/25 of a fluid ounce of blue to make 1 1/30 fluid ounces of purple how many fluid ounces of red paint ounces of red paint will she need to make 3 fluid ounces of purple paint