Solve for U in the equation D = (3/7)(U - 10)
D = (3/7)(U - 10)
Divide both sides by 3/7 which is the same as multiplying by the invert or 7/3
7/3D = U - 10
Add 10 to both sides
7/3D + 10 = U
or
U = 7/3D + 10
