please help me!

Question

A scatter plot of data comparing the number of years since Holbrook High

School introduced a math club and the number of students participating

contains the ordered pairs (3, 19) and (8, 42). Which is the slope-intercept

form of an equation for the line of fit containing those points?

Answer 1

A quick way to find the slope is comparing the y values then the x values, going in the same direction.

- for the y's, from 19 to 42, that's +23

- for the x's, from 3 to 8, that's +5

So the slope is 23/5. In a statistics problem like this, you could either leave it as a fraction, or turn it as the decimal 4.6

To find the y-intercept, take either of the points and the slope, and plug into y = mx + b, then solve for b. Let's take the first point

(3, 19)

y = mx + b

19 = 4.6(3) + b

19 = 13.8 + b

(Minus 13.8 on both sides)

5.2 = b

So the line is: y = 4.6x + 5.2, or y = 23/5 x + 26/5 as fractions.

*If you would like more math help, feel free to message me*

Answer 2

Slope intercept form is y = mx +b.

Whenever you have two points, you can acutally graph the two point and get you y-intercpet or b, and you slope, m, from the graph itself.

You can also find the slope from these two point using the slope forumals, m = (y2 - y1)/(x2 - x1), then you would need a point-slope formula to put the whole thing into slope incercept form.

E.I.

m = (42-19)/(8-3)

= 23/5

point-slope formula; y - y1 = m(x- x1), here, you can use any point

y - 42 = 23/5 (x - 8)

y - 42 = 23x/5 - 184/5, after you distribute in,

y = (23/5)x - 184/5 + 42

y = (23/5)x + (26/5), after you add 42 to a negative 184/5, which 26/5

Final answer is y = (23/5)x + 26/5