Answer:
<u>There would be 11 books in each stack, to have the same number.</u>
Step-by-step explanation:
1. Let's review the information given to us to answer the question correctly:
Books in stack 1 = 15
Books in stack 2 = 9
Books in stack 3 = 9
2. If the books were rearranged so that the stack had the same number of books how many books would be even?
Total books = Books in stack 1 + Books in stack 2 + Books in stack 3
Total books = 15 + 9 + 9
Total books = 33
Total books/Number of stacks = Number of books per stack to be the same
33/3 = Number of books per stack to be the same
<u>Number of books per stack to be the same = 11</u>
Answer:
6) x=9.75
10) Triangle OMN ~ Triangle ODK; SSS ~
11) SSS ~ theorem
12) SSS ~ theorem
Step-by-step explanation:
For #6, since the polygons are similar, then it must mean AD is congruent to JM and CD is congruent to LM. Now we can set up the proportion 39/20=x/5 and solve. Solving for x gets us x=9.75, so C is the correct choice
For #10, there's no information about angles whatsoever in the diagram, so B and C must be wrong. D must be wrong as well because if the triangles weren't similar, then why is OJ ~ JM and OK ~ KN? So thus, the triangles are similar by SSS.
For #11, this is sort of a no-brainer because there's no mention of angles, so D must be correct.
For #12, same concept, no mention of angles, all sides are similar to their respective sides of the different triangles, so A is correct.
Answer: The area of the triangle with the perimeter of 540 cm is approximately 10200 cm²
More exactly: 10182 cm²
Step-by-step explanation: 
240 × 84.85 = 10182
To get the height of the triangle, it takes some trigonometry;
Given 3 sides of a triangle, it is possible to calculate the angles using the Law of cosines and the formula 
We will need the measure of angle A, then use the sine of A to get the height of the line from angle C perpendicular to the base, side b.
We can use the dimensions given in the proportions and then multiply by 10 because the sides given add to a perimeter of 54, one tenth of the 540 cm of the actual triangle. The angles of the similar triangles are congruent.
side a = 19, side b = 24, side c = 11
24² + 11² - 19² is 576 + 121 - 361 = 336
2(24)(11) = 528
cos A = 336 / 528 that is 0.636364
= 50.47°
sin(50.47) = 0.77129
0.77129 × 11 = 8.48 is the height Rounding to 8.5 would be reasonable for this height
Using rounded values here to calculate Area :
85 × 240/2 = 10200 cm²