# graphing linear equations with just one intercept

#### cougar77d

##### New member
can anyone help me with my homework?
i need to graph linear equations with just one intercept. like; -4x+5y=o, and y=2x
can anyone help me?

#### o_O

##### Full Member
What do you mean by "with just one intercept"?

Are you graphing those individually? Easiest way would be to find the x-intercept (by solving for x when y = 0) and the y-intercept (by solving for y when x = 0) and connect them with a line, extending both ways.

#### cougar77d

##### New member
one intercept as in, through the zero. my teacher said to use whatever numbers i wanted to but i still dont get it.

#### o_O

##### Full Member
Oh sorry, didn't pay attention to your equations. Both of them only "just have one intercept." So just pick any other point and connect the origin (0,0) with the other point.

#### cougar77d

##### New member
ok. but how do i do that using whatevr numbers i want?

#### o_O

##### Full Member
What do you mean? Lets say for the equation -4x + 5y = 0. Choose any number for x and solve for y to get its corresponding value. This gives you another set of numbers, a coordinate point, which satisfies the equation. Then, connect the two points with a line.

#### cougar77d

##### New member
so multiply -4 by whatever number i choose then add/subtract it on both sides of the =sign, then divide that by 5?

#### o_O

##### Full Member
Yep. Solving for y. It's an equation. If you already know the value of x (which you chose) then you just use simple algebra to find the corresponding y value.

#### cougar77d

##### New member
so lets say i chose 20 to represent x, the number i get out of the 20 over 5 then represent y?

#### cougar77d

##### New member
could i use the y=mx+b formula for this?

#### o_O

##### Full Member
Sure but it's essentially the same thing. You're plugging in x = 20 to get some value for y. So if you chose x = 20:

-4(20) + 5y = 0
-80 + 5y = 0
etc. etc.

Usually, you use smaller x values so that your axes are easier to deal with. So maybe x = 5?

Also, if you really want you could put it into the y = mx + b form.
-4x + 5y = 0
5y = -4x
y = -4x/5

Same result either way.

#### cougar77d

##### New member
sorry. i didnt mean 4(20), i just meant the answer of 20. ok thank you.