Question

What is the justification for the step taken from line 2 to line 3?

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A) the subtraction property of equality
B) the multiplication property of equality
C) combining like terms on one side of the equation
D) the distributive property​

Answer 1

Answer: A

Explanation:

Answer 2

Option A.

Explanation:

We will write all the justifications for each step

Step 1 to step 2.

3x + 9 - 7x = x + 10 + x

-4x + 9 = 2x + 10

combining like terms on each side of the equation.

Step 2 to step 3.

-4x + 9 = 2x + 10

-6x + 9 = 10

Here [-4x - 2x + 9 = 2x - 2x + 10]

So, the subtraction property of equality is the justification.

Step 3 to step 4.

-6x + 9 = 10

-6x = 1

Here [ -6x + 9 - 9 = 10 - 9]

So subtraction property of the equality is followed.

Step 4 to step 5.

x = -
`(1)/(6)`

here [
`(6x)/(6)=-(1)/(6)`]

Division property of equality

Therefore, Option A. is true for the step 2 to step 3.