17=a-(-4)

Solution for 17=a-(-4) equation:

Simplifying
17 = a + -1(-4)

Multiply -1 * -4
17 = a + 4

Reorder the terms:
17 = 4 + a

Solving
17 = 4 + a

Solving for variable 'a'.

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

Add '-1a' to each side of the equation.
17 + -1a = 4 + a + -1a

Combine like terms: a + -1a = 0
17 + -1a = 4 + 0
17 + -1a = 4

Add '-17' to each side of the equation.
17 + -17 + -1a = 4 + -17

Combine like terms: 17 + -17 = 0
0 + -1a = 4 + -17
-1a = 4 + -17

Combine like terms: 4 + -17 = -13
-1a = -13

Divide each side by '-1'.
a = 13

Simplifying
a = 13