Pls halp. and also explain so i know your not trolling

Lilianna uses 3/4 calories per minute just by sitting. she uses 1 more calorie per minute by walking. lilianna uses a total of 12 1/4 calories walking to the park. lilianna uses the equation, d(.75+1)=12.25 to represent the situation. what does the variable d represent in the equation?

You can find the constant of proportionality by finding the ratio of

Reflect the point (7,0) across the y-axis