Question

Consider the following solution of 9x-7= -70

what properties of equality can justify the two steps in the solution


A.addition and division property

B. addition and multiply property

C. subrtraction and mutiply property

D. subtraction and division property

Answer 1

The solution 9x - 7 = -70 can be solved using the following steps:

Step 1: Add 7 to both sides of the equation to isolate the variable term:

9x - 7 + 7 = -70 + 7

Simplifying:

9x = -63

Step 2: Divide both sides of the equation by 9 to solve for x:

9x/9 = -63/9

Simplifying:

x = -7

The properties of equality that justify the two steps in the solution are:

Step 1: Addition property of equality, which states that adding the same number to both sides of an equation produces an equivalent equation. In this case, we added 7 to both sides of the equation.

Step 2: Division property of equality, which states that dividing both sides of an equation by the same non-zero number produces an equivalent equation. In this case, we divided both sides of the equation by 9.

Answer 2

• A. Addition and division property

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The first step involves addition of 7 to both sides and the second step involves division of both sides by 9.

They indicate the addition and division property of equality respectively.

Therefore correct choice is A.