Answer:
d = 0.33
Explanation:
First off, you want to get like terms next to each other. We'll move the numbers with variables on one side and normal numbers on the other. Since we're changing the sides of the equal sign they're on, this also changes whether their positive or negative.
d - d - 2d + 3d = 10 -7 + 8 - 10
Now that they're together, we can add or subtract them. The variables without numbers can be ones for this equation.
3d = 1
Now we divide 1 by 3 to find what d equals.
3d/3 = 1/3
d = 0.33