Better Students Ask More Questions.
3 Answers | add yours
3x-5 = 15-x
add x to both sides of the equation.
x+3x-5 = 15-x+x
3x+x-5 = 15
4x-5 = 15
add 5 to both sides
4x-5+5 = 15+5
4x = 20
Divide both sides by 4
4x/4 = 20/4
x = 5
The answer is x = 5
Posted by jeew-m on October 14, 2012 at 3:19 PM (Answer #1)
High School Teacher
Begin by combining your like terms (x) by adding x to each side
4x - 5 = 15
Add 5 to both sides in order to combine constants
4x = 20
Divide by 4 to isolate the variable
x = 5
Posted by kfcarter on October 14, 2012 at 10:45 PM (Answer #2)
Okay, when you are working an algebra equation, or an equation with variables in it, the first thing you want to do is get all "like" variables on the same side.
3x-5=15-x --> add x to both sides. (3x+x=4x; x+-x=1)
Rewrite the problem:
3x+x-5=15 ---> add like things together (3x+x=4x)
4x-5=15 ------> now add 5 to both sides (-5+5=1; 5+15=20)
Rewrite your problem:
4x=15+5 ----> add like things together! (15+5=20)
4x=20 -----> now in order to get x by itself divide both sides by 4.
4x/4=20/4 -----> 4x/4=x; 20/4=5
Rewrite the problem to get your answer!!!!
Hope this helps!!! :)
Posted by w0413860 on October 15, 2012 at 4:53 PM (Answer #3)
Join to answer this question
Join a community of thousands of dedicated teachers and students.