Expert: Josh - 4/17/2007

Question
could you help me with these
y=4+2x
x-3y=0
y=3x+5

Answer
Caroline,

You need to tell me what the question asks for. I cannot help you with ploting graphs, since it's impossible to do this in this forum. At best, I can only describe what each curve looks like.

First of all, these are all equations representing a straight line.

In general, straight lines may be written as y=mx+b, where m is the slope and b is the y-intercept (where the line crosses the y-axis when x=0).

i) y=2x+4, here slope is 2 (run over rise is 2 units up for every unit going from left to right). It crosses the y-axis at y=4, when x=0.

ii) Rewrite x-3y=0 as 3y=x. Dividing both sides by 3 gives y=(1/3)x. The slope is 1/3, it crosses the origin.

iii) is similar to i).