SOLUTION: in an isosceles triangle ABC base angles measure 2x+40 and 4x+10. Find the measure of each angle in triangle ABC

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Question 920619: in an isosceles triangle ABC base angles measure 2x+40 and 4x+10. Find the measure of each angle in triangle ABC
Found 2 solutions by stanbon, jim_thompson5910:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
in an isosceles triangle ABC base angles measure 2x+40 and 4x+10. Find the measure of each angle in triangle ABC
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base angles are equal.
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Equation::
2x+40 = 4x+10
2x = 30
x = 15
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2x+40 = 2*15+40 = 30+40 = 70
4x+10 = 4*15+10 = 60+10 = 70
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The 3rd angle = 180-2*70 = 40 degrees
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Cheers,
Stan H.
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Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
In every isosceles triangle, the base angles are congruent. In other words, they are equal.

2x+40 = 4x+10

40 = 4x+10-2x

40-10 = 4x-2x

30 = 2x

2x = 30

x = 30/2

x = 15

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Plug in x = 15: 2x+40 = 2(15)+40 = 70

Each base angle is 70 degrees

There are 2 of them, so they total in 2*70 = 140 degrees

The missing angle is 180 - 140 = 40 degrees

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Summary:

Base Angle 1: 70 degrees
Base Angle 2: 70 degrees
Vertex Angle: 40 degrees


Let me know if you need more help or if you need me to explain a step in more detail.
Feel free to email me at jim_thompson5910@hotmail.com
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Thanks,

Jim