-8r - 2 + 7r= -9solve the equation. then check the solution

1 answer:

8 0

The first step for solving this equation is to collect the like terms with an r variable.
-r - 2 = -9
Now move the constant to the right side of the equation and then change its sign.
-r = -9 + 2
Calculate the sum on the right side of the equals sign.
-r = -7
Then lastly,, change the signs on both sides of the equation to find your final answer.
r = 7
This means that the correct answer to your question is going to be r = 7.
We can check this by putting 7 where r is in the equation. This means that in order to check this,, our equation will change to the following:
-8(7) - 2 + 7(7) = -9
We will first start checking this by multiplying the first two numbers together.
-56 - 2 + 7(7) = -9
Now multiply the 7 by the number in the parenthesis.
-56 - 2 + 49 = -9
Now use addition and subtraction rules to calculate the expression on the left side of the equals sign.
-9 = -9
This tells us that the equality us true because both sides of the equation are identical.
Let me know if you have any further questions.
:)

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Extra info (optional section):

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