Question

If c = 7, then the value of b is...

Answer 1

3.5

Explanation:

The triangle shown is a 30-60-90 special right triangle. All right triangles that have a 30-degree angle will be, but if needed you can use the equation: 180 - (90 + 30) = x, to find the missing angle.

Special Right Triangles

Special right triangles are useful because they allow us to easily find missing sides without having to use sin, cos, or tan. All special right triangles have formulas that can be used to find missing sides.

Formulas

30-60-90 triangles have 3 sides: the hypotenuse (c), the short leg (b), and the long leg (a).

The formulas are as follows:

• c = 2b
• b = 0.5c
• a = b
  `√(3)`

Solving for b

We are already given c, so the easiest way to find b is to use the formula b = 0.5c. Just plugin the c-value.

• b = 0.5(7)

Once simplified the final answer is

• b = 3.5