Please help, I do not understand this

Step-by-step explanation:

The sin(30) = 1/2

The sin(30) = 1/2 = opposite / hypotenuse

Opposite = 7

hypotenuse = opposite / sin(30)

hypotenuse = 7 / (1/2) = 7 *2 / 1 = 14

The long side can be found using the Pythagorian Theorem.

a^2 + b^2 = c^2

a = 7

b = ?

c = 14

14^2 = 7^2 + b^2

196 - 49 = b^2

147 = c^2

147 = 3*7 *7

sqrt(b^2) = sqrt(3*7*7)

b = 7 sqrt(3)

the answer is b. 60. each interior angle in 120, so the exterior angle must be 60 in order to add up to 180

step-by-step explanation: