You can "spend all but 20%" so that means you can spend up to 80% of your money (since 20%+80% = 100%). Apply 80% to the value 225
80% of 225 = (80/100)*225 = 0.80*225 = 180
The most you can afford to spend is $180
9 goes into 695 in 2 times
If you want it in that format and simplified, this is it. y=-x+3
If you dont need it simplified then the answer is 2y=-2x+6