SOLUTION: The second angle in a triangle is half as large as the first. The third angle is three times as large as the second. Find the angle measures

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Question 848367: The second angle in a triangle is half as large as the first. The third angle is three times as large as the second. Find the angle measures
Answer by pmesler(52) About Me  (Show Source):
You can put this solution on YOUR website!
First, remember that the sum of all the angles in a triangle must equal 180 degrees.
Let x = the measure of the first angle
Let x/2 = the measure of the second angle
Let 3x/2 = the measure of the third angle.
Therefore

x + x/2 + 3x/2 = 180. Now solve for x. Once you find x, you will find the measure for all three angles.



x + x/2 + 3x/2 = 180
= x+ 4x/2 = 180
Multiply each side of the equation by 2 to get rid of the 2 in the denominator.

2[x + 4x/2] = 2(180).

2x + 4x = 360
6x = 360

Divide each side by 6

x = 60.

Therefore the first angle x, is 60 degrees. The second angle, x/2 = 60/2 = 30 degrees. The third angle 3x/2 = 3(60)/2 = 90.
60 + 30 + 90 = 180 so everything is correct.