2d+1.5a-4d-3.1a=

Solution for 2d+1.5a-4d-3.1a= equation:

Simplifying
2d + 1.5a + -4d + -3.1a = 0

Reorder the terms:
1.5a + -3.1a + 2d + -4d = 0

Combine like terms: 1.5a + -3.1a = -1.6a
-1.6a + 2d + -4d = 0

Combine like terms: 2d + -4d = -2d
-1.6a + -2d = 0

Solving
-1.6a + -2d = 0

Solving for variable 'a'.

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

Add '2d' to each side of the equation.
-1.6a + -2d + 2d = 0 + 2d

Combine like terms: -2d + 2d = 0
-1.6a + 0 = 0 + 2d
-1.6a = 0 + 2d
Remove the zero:
-1.6a = 2d

Divide each side by '-1.6'.
a = -1.25d

Simplifying
a = -1.25d