The area of a rectangular region is 6.2 × 10^3 square feet. The length

of the rectangular region is 1.55 × 10^2 feet. How much does it cost to

surround the region with a border that costs $0.80 per foot?

312

Step-by-step explanation:

First we need to determine the width

A = l*w

6.2 * 10 ^3 = 1.55 * 10 ^2 * w

Divide each side by 1.55 * 10 ^2

6.2 ^ 10 ^3  /1.55 * 10 ^2 = 1.55 * 10 ^2 * w / 1.55 * 10 ^2

Changing from scientific notation to standard

6200/155 = w

40 = w

Then we need to determine the perimeter

P = 2(l+w)

P = 2( 155+40)

P =2( 195)

P = 390

Now multiply by the price

390 *.80

312

f(x) = - 2/3x + 5; f(5/2)

substitute 5/2 in for x:

f(5/2) = -2/3(5/2) + 5

simplify the right side:

f(5/2) = -5/3 + 5

f(5/2) = 10/3

answer:

f(5/2) = 10/3

i hope this you!

option a is correct.

step-by-step explanation:

scale factor: it is used to find proportional measurements.

proportions means having the same ratio.

scale factor is the ratio of the model measurement to the actual measurement in a simplest form.

or we can say that the ratio of any two corresponding lengths in two similar geometric figures

if the scale factor is more than 1, then it is an enlargement,

if the scale factor less than 1, then it is a reduction.

given the two geometric figure:

by definition of proportions, we have