I rlly need help Graph y + 4 = 2/5 (x−3)

Question

Every time I graph it the number goes outside the graph.

It's a Graph to 10 btw

Answer 1

Hi Arnim!

Actually, you can use the 10 by 10 graph

dimensions if you do it this way.

First, notice that this equation is in

point-slope form.

(y-y₁) = m (x-x₁₎

2

(y+4) = -- (x - 3)

5

2

Where y₁= -4, x₁ = 3, and m = --

5

So, we have a point on the graph (x_1,y₁) = (3,-4)

2

and the slope m = --

5

We can use this information to graph.

First, plot (3,-4) on the graph.

The slope is positive, so that means the graph rises

as you move from left to right.

2 (change in y value is 2)

m = ---

5 (change in x value is 5)

From the point (3,-4), you are going to move up 2

and to the right 5

So, another point on the graph can be found from

this information: (3 + 5, -4 + 2) or (8,-2).

Plot (8,-2) and then you can draw a line between

this point and (3,-4).

Answer 2

First thing: you can always change the bounds of your graph. Most functions won't fit on a ±10 by ±10 graph. Don't feel limited by that. You have the freedom to scale the graph however you want!

Second thing: The easiest way to graph linear equations are to get it into y=mx+b (slope-intercept form). In slope intercept form m is the slope, and b is the y-intercept.

For this problem y+4=2/5(x-3),

first you distribute 2/5 to everything in the parentheses: y+4 = 2/5x - 6/5,

then get y by itself by subtracting 4 from both sides: y = 2/5x - 6/5 - 4.

Now you combine like term (remember to keep everything with an x alone!): y = 2/5x - 5.2

Now that we have it in slope-intercept form, graphing is much easier.

We know that the y-int is -5.2. This means when x is 0, y is -5.2.

Then you use the slope to go up 2 and to the right 5 to find your next point. Continue that for 3+ points and then connect the dots.

Quick tip, make the bounds of your graph go from 0 - 15 on the x-axis and 0 - -10 on the y-axis

Answer 3

Hi Arnim,

This function happens to have an x-intercept that is 13, which is outside of your graph region. It is ok to exclude the region of the graph where the line intersects the x axis, however if you really wanted to show it, you could work around this by giving each of your "ticks" along your axis a greater value.

So if you only had 10 ticks, as you say, you could give each one the value of 2 instead of 1, so that now your axis covers all the way up to the number 20 even though it has 10 ticks. Then you could find where the number 13 is on your newly designated x-axis tick values (it will be between two certain ticks in this case)