Question

help me please I've been stuck on this for hours I dearly need some help please help please help! I GIVE ALOT BRANLIES

Answer 1

Explanation:

Set up #21 as a proportion:

`(75)/(45) =(75+50)/(x)` which, simplified, is

`(75)/(45)=(125)/(x)` Cross multiply to get the height of the person on the right. That cross multiplication is

75x = 5625 so

x = 75 inches

Divide 75 by 45 to get the number of times taller the person on the right is than the person on the left. The person on the right is 1 2/3 times taller.

This is an enlargement, obviously, since the person on the right is definitely taller. He is 75 inches tall.

For #22 fill in the table for A, B, C like this:

A B C

3 6 9

-6 3 -3

Now multiply each number above by 2/3 to get the new coordinates, which are

A' B' C'

2 4 6

-4 2 -2

Graph these along with the original triangle and the new one should be 2/3 smaller than the first.

The one that is not an isometry in #23 is a dilation, C.

Answer 2

21. 5/3; enlargement; 75 inches

22. see attached

23. (C) a dilation

Explanation:

21. The figure on the right is larger than the original in the middle, so the dilation represents an enlargement.

The distance from C to P' is 50/75 = 2/3 longer than the distance from C to P. That means the scale factor is 2/3 more than 1.

The scale factor is 5/3.

Jay's dad is 5/3 times Jay's height, so is ...

(5/3)·(45 in) = 75 in . . . . height of Jay's dad

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22. See the attachment.

The coordinate matrix is filled in with the x-coordinate in the first row and the y-coordinate in the second row. The scalar multiplier to the left is the scale factor. It multiplies each term in the matrix to give the matrix on the right.

The change in coordinate values moves each image point to 2/3 of its previous distance from the origin.

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23. The word isometry comes from the Greek words isos and -metria, meaning equality of measure. An isometry is a figure in which the measures do not change. Since dilation changes the measures, a dilation is not an isometry.