HELP !! im going to post a picture of this math problem . i need an answer and explanation asap ..

The table shows the ratio between the number of books ordered and their cost: Number of Books Cost (dollars) 7 21 8 24 9 27 Find equivalent ratios when the number of books ordered is 1, 2, and 3. Write them as ordered pairs in the form (x-coordinate, y-coordinate). Starting from the origin, explain how to plot the three equivalent ratios on a coordinate grid.

Answer: Let the number of books be represented as x and the cost (dollars) be represented as y. From the table the ordered pairs in the form (x, y) can be gotten. (7, 21), (8, 24), (9, 27). To get the relationship between the number of books and the cost, we can use the formula of a straight line.

Using point (7, 21) and (8, 24):

$y-y_1=\frac{y_2-y_1}{x_2-x_1} (x-x_1)\\\\y-21=\frac{24-21}{8-7}(x-7)\\ \\y-21=3(x-7)\\\\y=3x-21+21\\\\y=3x$

When the number of books ordered is 1, 2, 3 the following pairs are:

For x = 1. y = 3x = 3(1) = 3

For x = 2 y=3x = 3(2) = 6

For x = 3 y = 3x = 3(3) = 9

The ordered pairs are (1, 3), (2, 6), (3, 9)

The graph is attached

To plot the ordered pairs, the number of books are plotted on the x coordinate and the cost on the y coordinate

8 0

3 years ago

What is the solution to the equation

Dimas [21]

Answer:

D) 21!

Step-by-step explanation:

So what we are dealing with here is some fractions that need to be made equal

Think about the fractions 1/2 and 2/4. They look different, right?

Well really, they are equal to another. All we need to do is simplify them!

If we divide the numerator and denominator (the top and bottom) of the fraction by, lets say, 2!

2 / 2 = 1

- -

4 / 2 = 2

And viola! It's been simplified down, and now we can see they are alike!

2 pieces of a pie cut in 4 pieces is the same as 1 piece of a pie cut in half!

(pro-tip, always try dividing a fraction by 2 first)

So now, using the same principal, we can solve this problem

By taking the denominators and dividing them like this:

35 / 5 = 7

We get 7! Now since we need to make these fractions equal, lets multiply the 7 we just got by the numerator of the second fraction, 3

7 x 3 = 21

So if we put the 21 over the 35, we get 21/35!

Thus, our answer is 21!

6 0

3 years ago

Y = f(x) = -3x Find f(x) when x=1.

brilliants [131]

Answer:

- 3

Step-by-step explanation:

Substitute x = 1 into f(x)

f(1) = - 3(1) = - 3 × 1 = - 3

7 0

3 years ago