A triangle has three angles. The first angle measures 20 less than a number. The second triangle is three times the number. The third is the number. What are the measurements of each of the three angles in this
triangle?

its 4 because 2 times 2 is 4, if you double the number two you get four

it's equivalent, so we can say that its equal.

let's call the denominator x and the numerador is 18 less then denominator, x - 18.

multiply

2.x = 5.(x - 18)

2x = 5x - 90

90 = 5x - 2x

90 = 3x

x = 90/3

x = 30

so:

the answer to your question is b.