If the current exchange rate is 2 British pounds for every U.S. dollar, a meal that costs $20 U.S. would cost a British visitor:

KIM [24]

We can't eliminate as is so we have to change something up there in the equations to get either the x values the same number but opposite signs, or the y values the same number but opposite signs. I chose to change the y values to the same number but different signs. In the first equation y is -3y and in the second one, y is -8y. The LCM of both of those numbers is 24, so we will multiply the first equation by an 8 (8*3=24) and the second equation by 3 (3*8=24) but since they are both negative right now, one of those multiplications has to involve a negative because - * - = +. Set it up like this:
8(-10x - 3y = -18)
-3(-7x - 8y = 11)
Multiply both of those all the way through to get new equations:
-80x - 24y = -144
21x +24y = -33
Now the y's cancel each other out leaving only the x's:
-59x = -177 and x = 3. Now plug that 3 into either one of the original equations to find the y value. Either equation will work; you'll get the same answer using either one. Promise. -7(3) - 8y = 11 gives a y value of -4. so your solution is (3, -4) or B above.

7 0

3 years ago

Read 2 more answers

a machine paints 340 toy boats in 45 minutes. Which expression equals the unit rate per hour? A: 3/4/340. B: 45/350 C: 340/3/4 D

monitta

340 in 0.75 hours. Divide both sides by 0.75, therefore 340/0.75 in 0.75/0.75 hour.
So 453.33 in one hour.(453.33 units per hour)

Hope it helps! :D

6 0

3 years ago

Read 2 more answers

12, 9, 15, 19, 20, 15<br><br> Mean <br><br> Median <br><br> Mode

Ede4ka [16]

Answer:

Mean: 15

Median: 15

Mode: 15

Step-by-step explanation:

<h2>Definitions:</h2>

<u>Mean</u>: It represents the average value of a given data set. The formula for finding the mean of a given set of numbers by taking the quotient of all numbers and the number of values. In other words:

$\displaystyle\mathsf{Mean\:=\:\frac{Sum\:of \:all\: values}{Number\:of\:values \:in\: a \:given \:data\:set}}$

<u>Median:</u> It represents the middle value in a given set of numbers. In order to determine the median, it is essential to arrange the given data either in <em>ascending</em> or <em>descending</em> order (although it is customary to arrange the numbers into ascending order).

If there is an odd number of values in a given set, then the <u>middle number</u> is the median of that set.

If a given list comprises of an even number of items, then we must take the <em>average</em> of the two middle numbers.

<u>Mode</u>: It represents the number that <u>occurs most often</u> on a list of items or data.

<h2>Solution:</h2><h3><u>Find the Mean:</u></h3>

Using the formula provided in the previous section for finding the mean:

$\displaystyle\mathsf{Mean\:=\:\frac{Sum\:of \:all\: values}{Number\:of\:values \:in\: a \:given \:data\:set}}$

$\displaystyle\mathsf{Mean\:=\:\frac{12+9+15+19+20+15}{6}\:=\:\frac{90}{6}\:=\:15}$

<h3><u>Find the Median:</u></h3>

Arrange the given data set in <u><em>ascending order</em></u>:

12, 9, 15, 19, 20, 15 ⇒ 9, 12, <u>15</u>, <u>15</u>, 19, 20

Next, since there is an even number of items on our given data set, we must <u>take the average of the</u><u> two middle numbers</u> (which are 15 and 15):

$\displaystyle\mathsf{Median\:=\:\frac{15+15}{2}\:=\:\frac{30}{2}\:=\:15}$

Therefore, the median is 15.

As described in the previous section of this post, the mode is the number that occurs most often on our given data. The only repeating number on our list is 15, hence it is the mode.

Therefore, the <em>mean</em>, <em>median</em>, and <em>mode</em> of the given data set is <u>15</u>.

6 0

3 years ago

Which pair shows equivalent expressions?

viva [34]

Answer:

b.

Step-by-step explanation:I think

3 0

2 years ago

How are determinants used to find areas of polygons?

ANTONII [103]

When you arrange the N points in sequence around the polygon (clockwise or counterclockwise), the area is half the magnitude of the sum of the determinants of the points taken pairwise. The N determinants will also include the one involving the last point and the first one.

For example, consider the vertices of a triangle: (1,1), (2,3), (3,-1). Its area can be computed as
(1/2)*|(1*3-1*2) +(2*-1-3*3) +(3*1-(-1)*1)|
= (1/2)*|1 -11 +4| = 3

4 0

3 years ago