The sum of the measures of the angles of a triangle is 180. The sum of the measures of the second and third angles is three times the measure of the first angle. The third angle is 15 more than the second. Let x, y, and z represent the measures of the first, second, and third angles, respectively. Find the measures of the three angles. Do not include the degree symbol in your answer.

x = 45

y = 60

z = 75

Step-by-step explanation:

We can create three different equations with the given variables:

x + y + z = 180

y + z = 3 x

z = y + 15

then we can use this last equation to substitute for 'z" in the second equation:

y + z = 3x

y + y + 15 = 3 x

2 y + 15 = 3 x

x = 2/3 y + 5

Then we can re-write the first equation in terms of y and solve for this unknown:

2/3 y + 5 + y + y + 15 = 180

2/3 y + 2 y = 160

8/3 y = 160

y = 3 * 160 /8

y = 60

Then   x = 2/3 (60) + 5 = 45

so x = 45

and finally:   z = 60 + 15 = 75

so  z = 75

what is the original number? you forgot to add it.