1. which of the following transformations are rigid motions?
( pick all that are needed)
a) reflection
b) dilation
c) rotation
d) translation

A) reflection   C) rotation    D) translation

Step-by-step explanation:

A rigid transformation happens when a point or object is moved, but the size and shape remain the same. There are four kinds of rigid transformation.

1) translation 2) reflection 3) rotation 4) glide reflection.

They all create congruent images.

But a dilation is a non rigid motion.

A dilation is a transformation that creates an image that is the exactly same shape as the original, but have a different size.

x = 10.1

step-by-step explanation:

all of the angles of a tirangle add up to 180º

180 - 65 = 115 (since we already know the value of one angle)

(2x + 7) + (8x + 7) = 115

(combins like terms) 10x + 14 = 115

(isolate the variable subtract 14 from both sides): 10x = 101

(find the variable divide both sides by 10): x = 101/10

x = 10.1

it is a. 4.2 because 7.6-3.4 gets the remaining length of 4.2. i might be wrong but i am pretty sure this is the answer.