This is about Reasoning Strategy, I really need help on this, I have a test tomorrow on it! Please help... Ok, here's what it says:

3a. What is the y-intercept of the trend line? (What do they mean???)
3b. Locate one other point on the trend line, then find the slope of the trend line (I don't know what they mean?)

...Please help.

3a. The y intercept is the value of y where x equals zero (where the trend line intercepts the y axis).

3b. Pick any other point on the trend line (besides the y intercept) and compute the slope as the change in y divided by the change of x.

ok, for 3b, I would need to divide any point in the x axis by a point on the y axis? Or is that wrong?

3a. The y-intercept is found when you set x to = 0. The y-intercept is the point where the graph of the line crosses the y-axis.

SAMPLE:

In the equation y = 3x + 5, what is the y-intercept?

It is the point (0,5). Do you see number 5? That number represents the y-intercept when x = 0.

Don't trust me?

Here it is:

Let x = 0.

y = 3(0) + 5

y = 0 + 5

y = 5

So, y became 5 when we set x to = 0.

====================================

3b. Pick any two points on the line and find the slope of the line.

The slope is a numerical value that describes just how slanted a given line is.

Here is is an example of finding the slope of a line.

SAMPLE:

Given the points (3, 4) and (8, 9), find the slope.

The symbol for slope is the letter m.

Let m = slope.

We now subtract b from d and a from c.

(a,b) = (3,4)

(c,d) = (8,9)

m = (9 - 4)/(8 - 3)

m = 5/5

m = 1

The slope is 1.

Did you follow?

Yep, thank you VERY much! Except that I don't really get 3a...

P(2,0) Q(4,4)

I'd be happy to help you understand these questions!

3a. What is the y-intercept of the trend line?
The y-intercept of a trend line is the point where the line intersects the y-axis. In other words, it is the value of y when x is equal to zero. To find the y-intercept of the trend line, you need to have the equation of the trend line. If you don't have the equation, you can find it by using two points on the line or by using the slope-intercept form (y = mx + b), where m is the slope and b is the y-intercept.

To find the y-intercept using two points on the line:
1. Choose two points on the trend line. You can select any two points that lie on the line.
2. Determine the coordinates of the two points (x1, y1) and (x2, y2).
3. Use the formula for the slope of a line, which is (y2 - y1) / (x2 - x1), to find the slope of the trend line.
4. Once you have the slope, use the coordinates of one of the points and the slope in the slope-intercept form (y = mx + b) to solve for b, which represents the y-intercept.

3b. Locate one other point on the trend line, then find the slope of the trend line.
To find the slope of a trend line, you need two points on the line. One point is already given, and you need to locate another point on the trend line. Ideally, you would have the equation of the trend line, as it makes finding additional points easier.

To find another point on the trend line:
1. If you have the equation of the trend line, substitute a value for x (other than the one you already have) into the equation to find the corresponding y-value. This will give you the coordinates of another point on the line.
2. If you don't have the equation, you can estimate the location of another point visually by looking at the graph and selecting a point that appears to be on the line.

Once you have two points on the trend line, use the formula for the slope of a line again, which is (y2 - y1) / (x2 - x1), to calculate the slope. The slope represents the rate of change of the dependent variable (y) with respect to the independent variable (x).