Help please due in 5 mins

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?

How do i make someone brainliest? (if you answer me, i might be able to make you brainliest! )

I’m stuck on this equation, anyone got the answer?