The answer you're looking for is .5 Hope it helps ;)
Area = 1/4√(5(5+2√5))a^2. a is the length of a side. If you plug in 10 as a, you get approximately 172, which is about the same as the 1st option .
Answer: (-infinity,10]
Step-by-step explanation: 50n is less than or equal to 500. So, treat the less than or equal to sign as an equal sign. Then do like regular and divide 500 by 50 to get ten on the right while N stays on the left. To get n is greater than or equal to 10!