Question

2. A line goes through the points (9, 10) and (-3, 2).
(a) What is the slope of the line? Show your work
(b) Write the equation of the line in point-slope form. Show your work
(c) Write the equation of the line in slope-intercept form. Show your work.

Answer 1

A.)
Slope = $\frac{y2-y1}{x2-x1}$
-------------------------------
Starting with Y's
2 - 10 = -8
---------------------------------------
Now X's
-3 - 9 = -12
-------------------------------------------
-8/-12 
Simplify
2/3 is your slope
==================================================================
B.)
I'm not to sure about this one so i'll just put the answer i got in case I get it incorrect =/ (8x + -12y = -48)
===================================================================
C.) Using the slope we already had (2/3) we can start our equation
Y = 2/3x + B
----------------------------------------------------------------------------------------
 but what is B? To find B we plug in the numbers of (9,10)
 y=mx+b or 10=2/3 × 9+b, or solving for b: b=10-(2/3)(9). b=4.
B is 4
------------------------------------------------------------------------------
Now make your equation y = 2/3x + 4