Answer:
A and C are proportional relationships.
Step-by-step explanation:
Recall that a "proportional relationship" has no constant term. Thus, we eliminate Answers B and D immediately.
Answer A represents a proportional relationship: y varies directly with the square of x.
Answer C also represents a proportional relationship: y varies directly with x.
Answer:

Step-by-step explanation:
So the question here is asking you to use the quadratic formula which is expressed as: 
A quadratic can generally be expressed as: 
So using the equation you gave: 
We can identify the following values: a=1, b=-5, c=-1
Btw the equation explicitly write "1" as the coefficient of x, but since it's not provided it's implied that it's 1.
So plugging in the known values, we get the following equation:

The last step just consists of taking the + and - solution, and since it asks for exact solutions you leave the 29 under the radical, and you don't approximate. There is no further simplification that can be done here.
Answer:
50°
Step-by-step explanation:
angle 5 = angle 4 ( Alternative Interior Angles are equal )
But angle 3 & angle 4 are linear pairs. So,
angle 3 + angle 4 = 180°
=> angle 3 + angle 5 = 180° (angle 5 = angle 4)
=> angle 3 + 130° = 180°
=> angle 3 = 180° - 130° = 50°
Yes it is linear since it's in the standard form Ax+By = C
A = 2
B = -8
C = 16
The area of a polygon is given by the formula Area = ap/2 where a is the length of the apothem and p is the perimeter. The apothem is a line from the center of the polygon perpendicular to a side.
Depending on the formula you know, you can find the length of a side in 1 of 2 ways.
The first way uses a triangle. Using the radius of the polygon you can create 8 congruent triangles. The center angle will be 360 / 8 = 45 and two side lengths of 20. You can find the length of the base using the law of cosines.
c^2 = 20^2 + 20^2 - 2(20)(20)(cos 45)
c^2 = 400 + 400 - 800(cos 45)
c^2 = 800 - 800(cos 45)
c = sqrt(800 - 800(cos 45)
c = 15.31
The second way is to use this formula:
r = s / (2 sin(180 / n))
20 = s / (2 sin(180/8)
(20)(2)sin(22.5) = s
(40)sin(22.5) = s
s = 15.31
We need to calculate the perimeter. As there are 8 sides (8)(15.31) = 122.48
Now we need to calculate the apothem using
a = S / (2 tan (180 / n)
a = 15.31 / (2 tan (180 / 8))
a = 18.48
Now solve for the area
Area = ap/2
Area = (18.48)(122.48)/2
Area = 1131.72
perimeter = 122.48
area = 1131.72