Unit Test Review

You spend $40 on a meal including tax and want to leave a tip that is 20% of the $40. What is the total cost, with the tip?

fenix001 [56]

Your total would be $48.00

7 0

2 years ago

Read 2 more answers

A environmental initiative has the goal of saving at least 25 2525 million hectares of rainforest through both planting trees an

Anestetic [448]

Answer:

The possible way for the initiative to accomplish its goal without exceeding its budget is use 12.5 hectares for planting trees and 12.5 hectares by purchasing land.

Step-by-step explanation:

Let the variable X represent the amount of land used for planting trees and Y represent the amount of land purchased.

The goal of the environmental initiative is to save at least 25 million hectares of rain forest.

That is:

X + Y = 25....(i)

Now it is provided that:

The cost of planting trees is $ 400 per hectare.
The cost of purchasing land is $ 260 per hectare.
The initiative has a budget of $8,250 million.

Using the above data it can be said that:

400X + 260Y = 8250....(ii)

Solve equations (i) and (ii) simultaneously.

$\ \ \ \ x+y=25]\times 260\\400x+260y=8250\\\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\\\\\Rightarrow\\\\260x+260y=6500\\400x+260y=8250\\(-)\_\_\_\_\_\ (-)\_\_\_\_(-)\_\_\_\\\\\Rightarrow\\\\-140x=-1750\\\\x=\frac{1750}{140}\\\\x=12.5$

Then the value of y is:

$x+y=25\\y=25-x\\y=25-12.5\\y=12.5$

Thus, the possible way for the initiative to accomplish its goal without exceeding its budget is use 12.5 hectares for planting trees and 12.5 hectares for purchasing land.

4 0

3 years ago

Which graph shows the result of dilating this figure by a factor of 4 about the origin? On a coordinate plane, rectangle A B C D

Andrei [34K]

Answer:

Second option: On a coordinate plane, rectangle A'B'C'D' prime has points $(-4,4),(12,4),(12,-4),(-4,-4)$

(See the graph attached)

Step-by-step explanation:

For this exercise it is importnat to know that a Dilation is defined as a transformation in which the Image (The figure obtained after the transformation) has the same shape as the Pre-Image (which is the original figure before the transformation), but they have different sizes.

In this case, you know that the vertices of the rectangle ABCD ( The Pre-Image) are the following:

$A(-1,1)\\\\B(3,1)\\\\C(3,-1)\\\\D(-1,-1)$

Therefore, to find the vertices of the rectangle A'B'C'D' (The Image) that results of dilating the rectangle ABCD by a factor of 4 about the origin, you need to multiply the coordinates of each original vertex by 4. Then, you get:

$A'=((-1)(4),(1)(4))=(-4,4)\\\\B'=((3)(4),(1)(4))=(12,4)\\\\C'=((3)(4),(-1)(4))=(12,-4)\\\\D'=((-1)(4),(-1)(4))=(-4,-4)$