3-9(1-7d)=-31

Solution for 3-9(1-7d)=-31 equation:

Simplifying
3 + -9(1 + -7d) = -31
3 + (1 * -9 + -7d * -9) = -31
3 + (-9 + 63d) = -31

Combine like terms: 3 + -9 = -6
-6 + 63d = -31

Solving
-6 + 63d = -31

Solving for variable 'd'.

Move all terms containing d to the left, all other terms to the right.

Add '6' to each side of the equation.
-6 + 6 + 63d = -31 + 6

Combine like terms: -6 + 6 = 0
0 + 63d = -31 + 6
63d = -31 + 6

Combine like terms: -31 + 6 = -25
63d = -25

Divide each side by '63'.
d = -0.3968253968

Simplifying
d = -0.3968253968