-14=-20y-7x<br> 10y+4=2x <br><br> Solve by Elimination please!

Dimas [21]

Answer: 2 1590909/ 5000000

5 0

3 years ago

Elena bikes 20 minutes each day for exercise. Write an equation to describe the relationship between her distance in miles, D, a

kompoz [17]

<u>Answer:</u>

The equation to describe the relationship between Elena distance:

a) D = 4.34 miles, b) D = 4.25 miles and c) 12D = M + 3N miles.

<u>Solution:</u>

Given, Elena bikes 20 minutes each day for exercise.

We have to write an equation to describe the relationship between her distance in miles, D, and her biking speed, in miles per hour,

We know that, distance travelled = speed $\times$ time

a. At a constant speed of 13 miles per hour for the entire 20 minutes

Her speed is 13 miles per hour.

Then, distance D miles = 13 miles per hour $\times$ 20 minutes

$\mathrm{D}=13 \text { miles per hour } \times \frac{20}{60} \text { hours } \rightarrow \mathrm{d}=13 \times \frac{1}{3} \rightarrow \mathrm{d}=4.34 \text { miles approximately. }$

b. At a constant speed of 15 minutes per hour for the first 5 minutes, then at 12 miles per hour for the last 15 minutes

Now, total distance travelled = distance travelled with 15 mph + distance travelled with 12 mph

$\begin{array}{l}{\mathrm{D}=15 \mathrm{mph} \times 5 \text { minutes }+12 \mathrm{mph} \times 15 \text { minutes }} \\\\ {\mathrm{D}=15 \mathrm{mph} \times \frac{5}{60} \text { hours }+12 \mathrm{mph} \times \frac{15}{60} \text { minutes }} \\\\ {\mathrm{D}=15 \times \frac{1}{12}+12 \times \frac{1}{4} \rightarrow \mathrm{D}=\frac{5}{4}+3 \rightarrow \mathrm{D}=3+1.25 \rightarrow \mathrm{D}=4.25 \mathrm{miles}}\end{array}$

c. At a constant speed of M miles per hour for the first 5 minutes, then at N miles per hour for the last 15 minutes

Now, total distance travelled = distance travelled with M mph + distance travelled with N mph

$D = M mph \times 5 minutes + N mph \times 15 minutes$

$\mathrm{D}=\mathrm{M} \mathrm{mph} \times \frac{5}{60} \text { hours }+\mathrm{N} \mathrm{mph} \times \frac{15}{60} \text { minutes }$

$\mathrm{D}=\mathrm{M} \times \frac{1}{12}+\mathrm{N} \times \frac{1}{4} \rightarrow \mathrm{D}=\frac{M}{12}+\frac{N}{4} \rightarrow \mathrm{D}=\frac{M}{12}+\frac{3 N}{12} \rightarrow 12 \mathrm{D}=\mathrm{M}+3 \mathrm{N} \text { miles }$

Hence, a) D = 4.34 miles, b) D = 4.25 miles and c) 12D = M + 3N miles.

8 0

4 years ago

The circle below is a representation of a (huge) tire.

arsen [322]

1. 2πr=C=6πft
2. 50rev* 6π/1rev= 300πft approximately 942 ft.

7 0

4 years ago

What is the value of the expression: 4^2 +4^2 +2^2

fgiga [73]

Answer:

Step-by-step explanation:

4^2 = 4 * 4 = 16

2^2 = 2 * 2 = 4

4^2 +4^2 +2^2 = 16 + 16 + 4 = 36

8 0

3 years ago

Read 2 more answers

Please hurry!! Select all that apply.<br> To write a percent as a decimal..

igomit [66]

Answer:

<h2>Divide by 100</h2><h2>and</h2><h2>Move the decimal point two places to the left</h2>

Step-by-step explanation:

__________________________________________________________

According to <em>Calculator Soup,</em>

<em>Divide a percent by 100 and remove the percent sign to convert from a percent to a decimal. The shortcut way to convert from a percentage to a decimal is by removing the percent sign and moving the decimal point 2 places to the left. Express 50% as a decimal. "Percent" means "per 100" or "over 100".</em>

<em>The answers are Divide by 100 and Move the decimal point two places to the left.</em>

<em>Hope this helps! <3</em>

5 0

3 years ago

-14=-20y-7x 10y+4=2x Solve by Elimination please!