When solving an equation, Carmen's first step is shown below. Which property justifies Carmen's first step? \text{Original Equation:}

Original Equation:

-2(7x^2-1)+6 =

−2(7x

2

−1)+6=

\,\, 8x^2-10

8x

2

−10

\text{First Step:}

First Step:

(7x^2-1)-3 =

(7x

2

−1)−3=

\,\, -4x^2+5

−4x

2

+5