-10b^2-(-9b^2-4)=

Solution for -10b^2-(-9b^2-4)= equation:

Simplifying
-10b2 + -1(-9b2 + -4) = 0

Reorder the terms:
-10b2 + -1(-4 + -9b2) = 0
-10b2 + (-4 * -1 + -9b2 * -1) = 0
-10b2 + (4 + 9b2) = 0

Reorder the terms:
4 + -10b2 + 9b2 = 0

Combine like terms: -10b2 + 9b2 = -1b2
4 + -1b2 = 0

Solving
4 + -1b2 = 0

Solving for variable 'b'.

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

Add '-4' to each side of the equation.
4 + -4 + -1b2 = 0 + -4

Combine like terms: 4 + -4 = 0
0 + -1b2 = 0 + -4
-1b2 = 0 + -4

Combine like terms: 0 + -4 = -4
-1b2 = -4

Divide each side by '-1'.
b2 = 4

Simplifying
b2 = 4

Take the square root of each side:
b = {-2, 2}