D. X = 10
6x-20= 40
6x=40+20
6x=60
X=10
Answer: doug has 16 cards
Step-by-step explanation: 12+4=16
Give brainliest if it help :)
Answer:
(a) is 4*C and (B) is 16*C
Answer:x=5 or x=−5
Step-by-step explanation:Step 1: Take square root.
x=±√25
x=5 or x=−5
The answer is: A
A decagon is a 10-sided polygon, with 10 interior angles, and 10 vertices which is where the sides meet. A regular decagon has 10 equal-length sides and equal-measure interior angles. Each angle measures 144°