Question

Can anyone help me? My teacher just recently taught me this today, be he never explained much. The question is in the photo

Answer 1

You've got five different problems in this photo ... four on top and the word problem on the bottom ... and they're all exactly the same thing:  Taking two points and finding the slope of the line that goes through them.

In every case, the procedure is the same.
If the two points are  (x₁ , y₁)  and  (x₂ , y₂) , then
the slope of the line that goes through them is

                          Slope  =  (y₂ - y₁) / (x₂ - x₁) .

This is important, and you should memorize it.

#1).  (8, 10)  and  (-7, 14)

         Slope  =  (14 - 10) / (-7 - 8)  =  4 / -15

#2).  (-3, 1)  and  (-17, 2)

         Slope  =  (2 - 1) / (-17 -  -3)  =  (2 - 1) / (-17 + 3)  =  1 / -14

#3).  (-20, -4)  and  (-12, -10)

         Slope  =  [ -10 - (-4) ] / [ -12 - (-20) ]

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

The word problem:

This question only gives you one point on the graph,
and then it wants to know what's the slope ?
What are you going to do for another point ?

A "proportional relationship" always passes through the origin,
so another point on the line is  (0, 0) .

Now you have two points on THAT line too, and you can easily
find its slope.