All categories

3 years ago

How to solve this? Help me please

Mathematics

1 answer:

Korvikt [17]3 years ago

5 0

The answer is C. 650

<em>-</em><em>Kearsi</em>

You might be interested in

Jean runs 8 mi and then rides 11 mi on her bicycle on a biathlon. She rides 9 mph faster than she runs. If the total time for he

Ipatiy [6.2K]

Let Jean's speed while running = x mph

Then Jean's speed while riding will be = x+9 mph

Distance covered by running = 8 miles

Distance covered by riding = 11 miles

Total time taken to complete the race = 1.5 hours

As, $time=\frac{distance}{speed}$

So, time for running= $\frac{8}{x}$

And time for riding= $\frac{11}{x+9}$

Equation becomes:

$\frac{8}{x}+\frac{11}{x+9}=1.5$

Now, multiply every term by 2x(x+9) to clear denominators:

$16(x+9)+22x=3x(x+9)$

Simplifying it we get

$3x^{2}-11x-144=0$

Solve the quadratic equation using formula

$x= \frac{-b+\sqrt{b^{2}-4ac }}{2a}$

putting a=3 , b= -11, c= -144

we get (x - 9)(3x + 16) = 0

where x=9 and x= $\frac{-16}{3}$

Neglect the negative answer as speed cannot be negative, so x = 9 mph

Hence, Jean's running speed is 9 mph and riding speed is x+9 = 9+9 = 18 mph

4 0

4 years ago

56 points for whoever answers correctly !

vladimir2022 [97]

We need to use what we know about rectangles to get:

Total length = 2*W + 8ft
Total width = W + 8ft

2) area = 2*W^2 + 24ft*W + 64ft^2

<h3>Working with rectangles:</h3>

We know that rectangles are defined by two measures, width W and length L.

Here we do know that the length of the pool is twice the width, and the width is W, then the length of the pool is:

L = 2*W

And we also have a sidewalk of 4ft all around the pool, now we want to get:

1) The total length and the total width.

This will be equal to the length/width of the pool <u>plus twice the width of the sidewalk</u> (we add it twice because is in both ends) then we have:

Total length = L + 2*4ft = 2*W + 8ft
Total width = W + 2*4ft = W + 8ft

2) Now we want to get an expression for the total area of the pool.

Remember that for a rectangle the area is just the product between the width and the length, so to get the area of the pool with the sidewalk we just take:

area = (total length)*(total width)

area = (2*W + 8ft)*(W + 8ft) = 2*W^2 + 3*W*8ft + 64ft^2

area = 2*W^2 + 24ft*W + 64ft^2

This is the equation that gives the total area as a function of W, the width of the pool.

If you want to learn more about rectangles, you can read:

brainly.com/question/17297081

6 0

3 years ago

Suppose you know the perimeter of n octagons arranged as shown. What would you do to find the perimeter if 1 more octagon was ad

kogti [31]

As shown in the figures given :

For Figure 1 : perimeter = 8 units [As can be seen in the figure]

For figure 2(with 2 octagons) : perimeter = 8 × 2 - 1 = 15 units [since 1 side is common ]

For figure 2(with 3 octagons) : perimeter = 8 × 3 - 2 = 22 units [since 2 sides is common ]

If one more octagon is added

then perimeter = 8 × 4 - 3 = 29 units [since 3 sides will be common ]

3 0

3 years ago

Ayo late night sneaker meet up let’s see who we about to finesse

trapecia [35]

Answer:

what is this supposed to mean??

Step-by-step explanation:

3 0

3 years ago

What Is the percent equal to 3/10

lianna [129]

30 %
3/10 * 10 = 30/100
30/100= 30%

6 0

3 years ago