Answer as many as possible please need work for brainilist

1. 18x + 35y = 598

  x + y = 20

  Isolate a variable in the second equation:

  y = -x + 20

  Plug y back into the first equation

  18x + 35(-x + 20) = 598

  18x - 35x + 700 = 598

  -17x +700 = 598

  -17x = -102

   x = 6

   You carpool 6 days of the 20

   6 + y = 20

   y = 14

   You ride the bus 14 days of the 20

2.   4.50n + 3p = 252

     p = 2n

     Substitute p into the first equation

     4.50n + 3(2n) = 252

     4.50n + 6n = 252

      10.5n = 252

      n = 24

      They sold 24 cans of nuts

      p = 2(24)

      p = 48

      They sold 48 boxes of popcorn

      The group sold, in total, 24 + 48 = 72 cans of nuts and boxes of popcorn.

3.  x - y = 3

    x + y = 8

    Isolate a variable

    x = y + 3

    (y + 3) + y = 8

    2y + 3 = 8

    2y = 5

    y = 2.5

    The average speed with wind is 2.5 mph

    x - 2.5 = 3

    x = 5.5

    The average speed without wind is 5.5mph

4. x + 8y = 22.8

   x + 6y = 18.6

   Isolate

   x = -8y + 22.8

   Substitute

   (-8y + 22.8) + 6y = 18.6

   -2y + 22.8 = 18.6

   -2y = -4.2

   y = -2.1

   The gas costs $2.10 per gallon

    x + 8(2.1) = 22.8

    x + 16.8 = 22.8

    x = 6

    The cost of the car was is $6.

5.  Cost = 9.99 + 2.49x

    Cost = 20.49 + 1.79x    

    To find which one is better, we need to set them equal to each other at first.

    9.99 + 2.49x = 20.49 + 1.79x

    9.99 + 0.70x = 20.49

    0.70x = 10.5

    x = 15

So, they cost the same at 15 rentals.

To find which one is the better deal let's see how much both cost after 16 rentals.

     Cost = 9.99 + 2.49(16)

              = 49.83

     Cost = 20.49 + 1.79(16)

              = 49.13

Therefore, Main Street is the better deal because after the equilibrium Main Street costs less than Big Video.

6.  x + y = 15

    .25x + .05y = 2.75

    Isolate

    x = -y + 15

    Solve

    .25(-y + 15) + .05y = 2.75

    -.25y + 3.75 + .05y = 2.75

    -0.2y + 3.75 = 2.75

    -0.2y = -1

    y = 5

    There are 5 nickels

     x + 5 = 15

     x = 10

     There are 10 quarters

7. x + y = 26

   x + .25y = 17

   Isolate

   x = -y + 26

   Substitute

   (-y + 26) + .25y = 17

   -0.75y + 26 = 17

   -0.75y = -9

   y = 12

   There are 12 quarters in his pocket

   x + 12 = 26

   x = 14

   There are 14 dollars

I hope this helps!!

- Kay :)

the range of a function is the range of y-values for which it is defined, or exists. given that we are only looking at the y-values, we can already discount the first two answers as they deal with the domain of the function (range of x-values).

now, what we need to do is find the smallest and highest y-values for which the function is defined. if you'd like, you could take a ruler and start at the very bottom of the graph, find the lowest point, then move the ruler higher and higher until you reach the highest point. doing so either in your head or with an actual ruler, we can see that the lowest y-value is -5 and the highest y-value is -1.

the question now remains as to whether they are included in the range (fourth answer) or excluded (third answer). the key here is to recognise whether they are marked with an open or a closed circle. since both (-2, -5) and (2, -1) are marked with a closed circle, they are points that exist on the graph and are thus included in the range (note that if they were marked with an open circle like (4, -2) then that would signify that there is a break in the graph at that point).

thus, the fourth answer, (y | -5 ≤ y ≤ -1), is correct.

also note that usually it is good practice to scan your eye inbetween the highest and lowest point for any breaks in the graph - we do have one here at (4, -2), however -2 is still included in the range because there is another point that is included in the graph with the same y-value, ie. point (1, -2).

i hope that but if you require any further explanation don't hesitate to comment below.