Question

The table shows the amount of money that Bradford saved in his savings account after different amounts of time.

Answer 1

Nice of you to offer 50 points

the constant of proportinality is the sloep or
$\frac{change(y)}{change(x)}$
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

Answer 2

The constant property of the equation is 12.5