The slope of a(n) _____ graphs represents acceleration.

Margo brought 7 pens from a book store some pens cost $3.00 EACH and the rest cost $4.00 . If she paid a total of 23.00 for the

Montano1993 [528]

Answer:

5

Step-by-step explanation:

Margo bought 7 pens for $23.

Some pens are $3 and some $4.

We need to find how many $3 pens she bought.

Let the number of $3 pens be represented by p and let the number of $3 pens be represented by r. So:

p = $3 and r = $4

Now we know 7 pens were purchased so is we add the number of $3 pens purchased to the number of $4 pens purchased, we will get 7.

p + r = 7

We know that the total cost of the pens is $23 so that equation would be found by takign the $3 pen multiplied by the number of $3 pens purchsed added to the $4 pen multiplied by the number of $4 pens purchsed, which equals $23.

$3p + $4r = $23

Now we have 2 equations and 2 unknowns.

p + r = 7

$3p + $4r = $23

Let's solve for r in the first equation.

p + r = 7 Subtract p from both sides.

p - p + r = 7 - p The p on the left cancels.

r = 7 - p

Now that we know r, we can substitute it into the second equation and solve for p.

$3p + $4r = $23

3p + 4( 7 - p) = 23 Multiply it out.

3p + 4*7 - 4*p = $23

3p + 28 - 4p = 23 Combine like terms.

3p - 4p + 28 = 23

- 1p + 28 = 23 Subtract 28 from both sides.

- p + 28 - 28 = 23 - 28

- p = - 5 Divide each side by -1

- p/- 1 = - 5/ - 1 The negative cancels on each side.

p = 5

We can see Margo bought 5 $3 pens.

For fun, let's solve for how many $4 pens she bought. We know p, so we plug it in the first equation and solve for r.

p + r = 7

5 + r = 7 Subtract 5 from each side

5 - 5 + r = 7 - 5

r = 7 - 5

r = 2

So Margo bought 5 $3 pens and 2 $4 pens!

8 0

3 years ago

What is 6/4 as a mixed number?

CaHeK987 [17]

1.5 because 6 goes in to 4 1.5 times

8 0

4 years ago

The perimeter of the flag is 2080 ft what is the flags width and length of the length is 420 ft greater than the width

hram777 [196]

Answer:

The length of the flag is 730 ft and the width is 310 ft

Step-by-step explanation:

The correct question is

The perimeter of the flag is 2080 ft what is the flags width and length if the length is 420 ft greater than the width

Let

L ----> the length of the flag

W ---> the width of the flag

we know that

The perimeter of the flag (rectangle) is equal to

$P=2(L+W)$

we have

$P=2,080\ ft$

so

$2,080=2(L+W)$

$1,040=L+W$ ----> equation A

$L=W+420$ ---> equation B

Solve the system by substitution

substitute equation B in equation A

$1,040=(W+420)+W$

solve for W

$1,040=2W+420$

$2W=1,040-420$

$2W=620$

$W=310\ ft$

Find the value of L

$L=W+420$ ----> $L=310+420=730\ ft$

therefore

The length of the flag is 730 ft and the width is 310 ft

5 0

3 years ago

What is the slope of the line that passes through the points (-4, -9) and (5, 3)

egoroff_w [7]

Answer:

4/3

Step-by-step explanation:

Moving from (-4, -9) to (5, 3), x (the 'run') increases by 9 from -4 to 5, and y (the 'rise') increases by 12 from -9 to +3. Thus, the slope of the line connecting the two points is

m = rise / run = 12/9 = 4/3

It may help to think of the change in x (9) as the horizontal leg of a right triangle and the change in y (12) as the vertical leg. Then

m = (vertical leg length) / (horizontal leg length) = 12/9 = 4/3

5 0

3 years ago

Mary bowled six games this week. Her scores were 138,151,198,147,156, and 173. What was her average for those

erica [24]

The average of scores is 160.5

Step-by-step explanation:

Mean is the sum of all values divided by the number of values.

Given scores are:

138,151,198,147,156, and 173

The formula for average score is given by:

$Avg = \frac{Sum}{items}$

Putting values

$Avg = \frac{138+151+198+147+156+173}{6}\\Avg = \frac{963}{6}\\= 160.5$

The average of scores is 160.5

Keywords: Mean, Average

Learn more about mean at:

#LearnwithBrainly

4 0

4 years ago