Given that the time taken to get to campus is inversely proportional to driving rate, let the time be t and rate be r, thus the function will be written as:'
t=k/r
where
k is the constant of proportionality given by:
k=tr
when r=20 mph, t=1.25 hrs
thus
k=20×1.25
k=25 miles
thus the formula is:
t=25/r
when r=55 mph, the value of t will be:
t=25/55
t=5/11 hours

3 0

3 years ago

The perimeter of a rectangle is 30 cm and its length is x cm. Find its area in terms of x. step by step explanation.

mars1129 [50]

Answer:

The area of the rectangle in terms of 'x' = 13x

Step-by-step explanation:

Perimeter = 30 cm

Length = x cm

Using the perimeter formula to find the width w.

$P=2(l+w)$

$P = 2l + 2w$

$2w = P-2l$

Dividing both sides by 2

$w\:=\:\frac{P}{2}-2$

as P = 30 cm

$w\:=\:\frac{30}{2}-2$

$w\:=\:15-2$

$w = 13$ cm

Using the formula of the rectangle area

$A = wl$

substitute w = 13 and l = x in the formula

$A=13\times \:x$

$A = 13x$

Therefore, the area of the rectangle in terms of 'x' = 13x

7 0

2 years ago

Simplify x²-49/3x+21

Vera_Pavlovna [14]

First, you factor and simplify (respectively) the numerator and denominator. Your equation becomes:

$\frac{(x-7)(x+7)}{3(x + 7)}$

Notice, there is a (x + 7) on both the top and the bottom. Because of this, they cancel each other out. What is left is your answer:

$\frac{(x-7)}{3}$

3 0

3 years ago

Read 2 more answers

A rectangle has a perimeter of 56 in. The length is four more than the width. What are the length and width of the rectangle

Aleks04 [339]

Answer:

Width = 12 in

Length = 16 in

Step-by-step explanation:

Let, the Width of the rectangle = w in

Now, the length of the rectangle = (w + 4) in

Now, Perimeter = 56 in

Also, we know that

Perimeter of the Rectangle = 2 (Length +Width)

or, 2 (Length +Width) = 56

⇒ 2(w + 4 +w) = 56

or, 4w =56 -8

width = 12 in

So, Length = w + 4 = 12 + 4 = 16 in

7 0

2 years ago