Question 261608
If y=5x, and you have an algebraic expression of 2x + 3y = 34, you would start out by plugging in the 5x for y in the equation: 2x + 3 (5x) = 34.  So you can see that you have 3 times 5x... That would be 15x.  So let's insert that:
2x + 15x = 34  So now, we can combine like terms.  17x = 34.  Now to get x by itself, we have to divide that side of the equation by 17.  Because any number over itself equals 1.  And when you have a variable like x standing alone, it really has an invisible 1 in front of it.  It's like saying x = 1x  They are the same.  So whatever you do to one side of the equation, you have to do to the other, to make them equivalent:
17x/17 = 34/17   

17/17 is crossed out, because that just equals an invisible 1, and that would leave us with:

x = 34/17  
34 divided by 17 is 2.  So the answer is: x = 2