Answer:
The answer would be 17
Step-by-step explanation:
The answer would be 17 because if you add 12 plus 5 That would be your answer
Let x = number of students in each of the remaining rows
266 = (10 x 20) + (5 x 8) + 2x
266 - (10 x 20) - (5 x 8) = 2x
266 - 200 - 40 = 2x
26 = 2x
x = 26/2
x = 13
The area of the triangle will then be 9 times as great.
The formula of the area of a triangle is 1/2bh, so if the base has been tripled and the height has been tripled, you're essentially multiplying 3 to the original equation twice (3 x 3 = 9).
A and b are both accurate
For a:

which is true
For b:

which is also true
First way
arcsin(1/4) means that 1/4 sin of the angle.
sin(α)=1/4
sin²α+cos²α=1
(1/4)²+cos²α=1
cos²α=1-1/16 =15/16
cosα=+/-(√15)/4
<span>Second way
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sin(α)=1/4 =opposite leg/hipotenuse
cos(α)=adjacent leg/hypothenuse
adjacent leg =√(hypotenuse²- Opposite²)=√(16-1)=√15
cosα=+/-√15/4
For one value of sinα, possible 2 values of cosα.