Linear functions have to have the same slope between any 2 points
find the slope betwen them
slope betwen 2 points (x1,y1) and (x2,y2) is
(y1-y1)/(x2-x1)
given
(1,12) and (3,9)
slope=(9-12)/(3-1)=-3/2
if we wanted to chek furthere, we check (3,9) and (5,6) and fnd that the slope is also -3/2
so
y=mx+b
m=slope
b=yint
y=-3/2x+b
find b
if x=1 then y=12
12=-3/2+b
add 3/2 both sides
12+3/2=b
13+1/2=b
26/2+1/2=b
27/2=b
y=-3/2x+27/2
try them
we have 2 x values
7 and 3
input them and see their outputs
for x=7
y=-3/2(7)+27/2
y=-21/2+27/2
y=6/2
y=3
(7,3) is a valid point
for x=3
hold a second, we already have a x=3
it is (3,9)
none of them
answer is (7,3)
Answer:
The slope is -1
Step-by-step explanation:
It's decreasing which means it's negative and it decreases by 1 every time x increases by 1.
This is the worksheet I’m doing https://www.manhassetschools.org/cms/lib8/NY01913789/Centricity/Domain/710/Aim%2082%20Pd%209%20KEY.pdf
The slope would represent the cost per minute, since m is the length of the call in minutes. Logically, D) Cost per minute, is the only one that would work. The connection cost would be just added in, and you wouldn't multiply the cost of having a phone line by how many minutes you're on the phone. The length of the call is already there, it's m, so that wouldn't work either. Therefore, D, cost per minute, is the logical answer. The slope in the equation represents D, cost per minute.
