ShmoopTube

Where Monty Python meets your 10th grade teacher.

Search Thousands of Shmoop Videos


Right Triangles and Trigonometry Videos 37 videos

Verifying Trig Identities
1730 Views

Verifying trig identities is important, especially when you're about to let one of them into the country—which is why they should keep their pass...

Tangent Half-Angle Formula
1362 Views

Mosquitos need their caffeine, just like the rest of us. Wouldn't think zipping around and stinging people all day long sap your energy?

SOHCAHTOA
4616 Views

Sine is the opposite over the hypotenuse; cosine is the adjacent over the hypotenuse; and tangent is the opposite side over the adjacent side....

See All

ACT Math 4.3 Trigonometry 243 Views


Share It!


Description:

ACT Math: Trigonometry Drill 4, Problem 3. What is the length of side b?

Language:
English Language

Transcript

00:02

Here's your shmoop du jour...

00:05

The sin of angle A equals 4/9. What is the length of side B?

00:09

And here are your options...

00:13

We know that the sin of an angle equals the opposite side divided by the hypotenuse. Here,

00:18

the sin of A equals 4/9, which means that a = 4 and c = 9. Now we just need to find B

00:24

We can do that by using the Pythagorean theorem...which

00:27

is A squared plus B squared equals C squared. We plug the values in, and get that 4 squared

00:32

plus B squared equals 9 squared. 16 plus B squared equals 81.

00:37

Subtract 16 from both sides, and we get that B squared equals 65.

00:42

Take the square root of both sides, and we have that B equals the square root of 65.

00:47

Which is answer choice C.

00:48

Easy.

Related Videos

Inequalities in Number Lines
3230 Views

ACT Math: Coordinate Geometry Drill 1, Problem 1. Which inequality is expressed by the number line?

ACT Math 3.1 Intermediate Algebra
1955 Views

ACT Math: Intermediate Algebra: Drill 3, Problem 1. Find the fifth number in the series.

ACT Math 3.1 Plane Geometry
2559 Views

ACT Math: Plane Geometry Drill 3, Problem 1. What is the area of the trapezoid shape in the video?

Surface Area of Cylinders
14741 Views

Haven't you always wondered how much cardboard it takes to encase a trunk warmer for your pet elephant?

Perimeter of Irregular Shapes
4864 Views

Want to figure out the area and perimeter of irregular shapes? Break them down into regular shapes. For example, a flower can be broken down into s...