nice of you to offer 50 points
the constant of proportinality is the sloep or
[tex] \frac{change(y)}{change(x)} [/tex]
x is independent variable and y is dependent variable
the independent variable influences the value of the dependent variable
in this case, the number of months influences the amount of money saved
to find the slope, you do
x=number of months
y=amount
we have
4months, $50
8 months, $100
18 months, $225
or
(x,y)
(4,50)
(8,100)
(18,225)
we can compare
the slope between the points (a,b) and (c,d) is
(d-b)/(c-a)
we can take the slope between any 2 points (assuming the slope is the same, which it is)
(4,50) and (8,100)
slope=(100-50)/(8-4)=50/4=25/2=12.5
the slope is 12.5
2nd option is the answer
