First setup the system of equations for the given case.
Let sandwich=x
and delivery fee =y
Equations are:
4x+y=33 Equation 1
8x+y=61 Equation 2
Subtract equation 1 from 2.
4x=28
x=7
Now substitute value of x in equation 1.
4(7)+y=33
28+y=33
y=5
So cost of single sandwich=$7 and Delivery fee=$5
Now cost of 12 sandwiches:
12x+y=85
Put y=5
12x+5=85
12x=80
x=6.67 which is less than 7. So, They are not able to get 12 sandwiches for $85.
So,
I'm assuming you want me to make a formula for figuring your points after any given month assuming that you use the site at least once a month and you don't spend your points.
After one month, you will have your base 100 points plus an additional 10 points.
100 + 10 = 110
After two months, you will have gained an additional 10.
110 + 10 = 120
We can put this into a function, where P is your points, and m is the number of months you use the site.
P(x) = 100 + 10m
So after 500 months, you will have:
P(x) = 100 + 10(500) = 5100 points!
This is identical with:
y = 100 + 10m
and
y = 10m + 100
So this can be graphed as a linear equation/function with a y-intercept of 100 and a slope of 10/1.
Answer:
A
Step-by-step explanation:
i learned this before
Answer:
The next step is to combine constants
Step-by-step explanation:
Answer: 
Remember: RISE/RUN (y/x). Lines that are increasing have a positive slope, and lines that are decreasing have a negative slope.
You can find the slope in two ways:
1. Useful if the line is graphed: count the units between 2 points on the line.
- Let's use the points (-1, 4) and (4, -4).
- (-1, 4) is 8 units higher than (4, -4) and 5 units to the left of (4, -4).
- Because the line is decreasing, the slope is negative.
- Therefore, the slope is
.
2. Useful if the line is not graphed: find the difference between the y-coordinate values divided by the difference of the x-coordinate values.
- Let's use the points (-1, 4) and (4, -4).

- Therefore, the slope is
.