Answer: D. an angle is in standard position if the vertex is at the origin of a rectangular coordinate system and the initial side lies along the positive x-axis.
Answer: 8
Step-by-step explanation: Speed is distance/time
18/3 = 6 miles per hour running
18/2 = 9 miles per hour biking
3 hour bike = 27 miles
1.50 hour run (0.50 because 30 minutes is half of an hour) = 9 miles
27 + 9/3 + 1.50 = 36/4.5 or 8
14 because i did the math and i was right
Okay, it's wrong because they forgot to do -2 times 3x.
The correct answer is

-2x-8
Hope i got is correct!
4y=16
y is the variable. If you were to solve the equation you would write the equation as 4(4)=16.