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