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36 votes
36 votes
Can someone give me a quick algebra lesson and solve this example for me?

Do I subtract or add the coefficients with variables together? I’m not sure which signs to use, I have the answer but I just don’t understand how to get it. Please show the answer in steps, thank you!

3x - 15 + 6x + 2 = 41

User Abhay Gupta
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2 Answers

11 votes
11 votes

Answer:

3x- 15+6x+2=41

or, 9x-13=41

or, 9x= 54

: x=6

User Jbccollins
by
2.6k points
19 votes
19 votes

Answer:

See below

Explanation:

Hi there!

>>Do I subtract or add the coefficients with variables together?

Add the terms with variables. In this case, the terms with variables are 3x and 6x. The communicative property of addition still holds true, so 3x+6x and 6x+3x are the same.

Do NOT subtract terms. If you do, let's take the 3x and 6x from the example above, doing either 3x-6x or 6x-3x would lead to the wrong answer.

Note: if you encounter a situation where if you have let's say, the terms -3x and 17x, -3x+17 and 17x + -3x are exactly the same (commutative property of addition still holds true). DO NOT do 17x - -3x or -3x-17x! Those would lead to the wrong answer.

Now,

We are given the following equation:

3x-15+6x+2=41

And we want to solve it for x

As stated above, we ADD the terms with coefficients together. So 3x+6x=9x.

The same is true for the numbers without variables; -15+2=-13

On the left, we have:

9x-13=41

Add 13 to both sides to remove it from the left side

9x=54

Divide both sides by 9 to isolate x

x=6

Hope this helps!

User Kurian Vithayathil
by
2.6k points
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