what is the justification for the step taken from line 2 to line 3? 3x + 9 - 7x = x + 10 + x -4x + 9 = 2x +…

what is the justification for the step taken from line 2 to line 3? 3x + 9 - 7x = x + 10 + x -4x + 9 = 2x + 10 -6x + 9 = 10 -6x = 1 x = -\\frac{1}{6} the subtraction property of equality the multiplication property of equality combining like terms on one side of the equation the distributive property

what is the justification for the step taken from line 2 to line 3? 3x + 9 - 7x = x + 10 + x -4x + 9 = 2x + 10 -6x + 9 = 10 -6x = 1 x = -\\frac{1}{6} the subtraction property of equality the multiplication property of equality combining like terms on one side of the equation the distributive property

Answer

Answer:

A. the subtraction property of equality

Brief Explanation:

From line 2 ($-4x + 9=2x + 10$) to line 3 ($-6x + 9 = 10$), $2x$ is subtracted from both sides of the equation. This follows the subtraction - property of equality which states that if $a=b$, then $a - c=b - c$. Here $a=-4x + 9$, $b = 2x+10$ and $c = 2x$.