Answer:

Step-by-step explanation:
The reference angle is an acute angle that angle in standard position makes with the positive x-axis.
The given angle in radians is

This angle is already acute and hence it is itself a reference angle.
The reference angle of any angle in the first quadrant is the same angle.
Answer:
20 units²
Step-by-step explanation:
The x-intercepts are symmetrically located around the x-coordinate of the vertex, so are at
1.5 ± 5/2 = {-1, 4}
Using one of these we can find the unknown parameter "a" in the parabola's equation (in vertex form) ...
0 = a(4 -1.5)² +12.5
0 = 6.25a +12.5 . . . . . simplify
0 = a +2 . . . . . . . . . . . divide by 6.25
-2 = a
Then the standard-form equation of the parabola is ...
y = -2(x -1.5)² +12.5 = -2(x² -3x +2.25) +12.5
y = -2x² +6x +8
This tells us the y-intercept is 8. Then the relevant triangle has a base of 5 units and a height of 8. Its area is given by the formula ...
A = (1/2)bh = (1/2)(5)(8) = 20 . . . . units²
Answer:
Length of the canal on the map is 16.4 centimeters.
Step-by-step explanation:
If actual length of Panama Canal = 20 kilometers
and length of the canal on map = 4 centimeters
Then scale factor = 
= 
= 
If the actual length of Panama Canal = 82 kilometers
Then the length of canal on the map = Actual length × Scale factor
= 
= 16.4 centimeters
Therefore, length of the canal on the map is 16.4 centimeters.
The logic is there are six sides to each die, so for each number on one die you can pair with six different numbers on the other die. Therefore, the probability of rolling a prime number on two dice is 15/36, which reduces to 5/12.