In your own words, explain what it means for a transformation to be a rigid motion? (Help me pleass)

When keisha installed a fence along the 200 foot perimeter of her rectangular back yard, she left an opening for a gate.in the diagram below, she used x to represent the length in feet of the gate? what is the value? a. 10 b. 20 c. 25 d. 30

Simplify this expression. 8x 16(x + y)

Masons cell phone company charges $0.12 for every text message he sends plus $2.50 per month if mason sent 25 messages this month how much money does he owe the one with the correct answer and explanation gets 10 points and is marked as the brainliest answer