Help with order of operations: solve 13+x/2=3x for x

[Jagrisgod]

Please help. Trying to understand order of operations in algebra. For example

13+x/2=3x for x. (X/2 being x over 2)

i know now it is done like a two part equation

how do I know to subtract 13 from both sides or multiply by 2 on both sides. What is the rule?

 

[Jagrisgod]

Need help with order of opps

Please help!

example:
13+x/2=3x for x (x/2 being x over 2)

i believe this is done like a 2 step equation.
I am confused at the correct order of operations.
how do I know if I subtract 13 from both sides or multiply 2 on both sides?
what is the rule.

 

[stapel]

Please help. Trying to understand order of operations in algebra. For example

13+x/2=3x for x. (X/2 being x over 2)

i know now it is done like a two part equation

how do I know to subtract 13 from both sides or multiply by 2 on both sides. What is the rule?

You don't "know". The choice is up to you!

 

[stapel]

is it as simple as in above post???

Yes. Why? What did you get when you tried it different ways?

 

[HallsofIvy]

Please help!

example:
13+x/2=3x for x (x/2 being x over 2)

i believe this is done like a 2 step equation.
I am confused at the correct order of operations.
how do I know if I subtract 13 from both sides or multiply 2 on both sides?
what is the rule.

You can do either first! If you subtract 13 from both sides first you get x/2= 3x- 13. You can then multiply both sides by 2 to get x= 6x- 26. Subtract 6x from both sides, -5x= -26. And, last, divide both sides by -5 to get x= 26/5.

Or you can multiply both sides by 2: 26+ x= 6x. (Notice that both numbers on the left, 13 and x/2, are multiplied by 2.) Now subtract x from both sides to get 26= 5x and then x= 26/5 again.

But is that really the equation you are asking about? If you mean (13+ x)/2= 3x, that's a completely different question! To do that, first multiply by 2 to get 13+ x= 6x. Subtract x from both sides to get 13= 5x. Finally divide by 5 to get 13/5. That is a different answer because it is a different equation.