SOLUTION: The second angle of a triangle is four times the first and the third is 5 degree more than twice the first. find the measures of the angle.

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Question 228463: The second angle of a triangle is four times the first and the third is 5 degree more than twice the first. find the measures of the angle.
Found 2 solutions by drj, mangeshpjoshi:
Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
The second angle of a triangle is four times the first and the third is 5 degree more than twice the first. Find the measures of the angle.

Step 1. The sum of the three angles for a triangle is 180 degrees.

Step 2. Let x be the first angle.

Step 3. Let 4x be the second angle since it's four times the first.

Step 4. Let 2x+5 be the third angle since it is 5 degrees more than twice the first.

Step 5. Then, x%2B4x%2B2x%2B5=180 since the sum of the angles is 180 degrees.

Step 6. Solving the equation x%2B4x%2B2x%2B5=180 yields the following steps

7x%2B5=180

Subtract 5 from both sides of the equation

7x%2B5-5=180-5

7x=175

x=25 4x=100 and 2x%2B5=55. Note these three angles add up to 180 degrees as a check.

Step 6. ANSWER: The angles of the triangle are 25, 100, and 55 degrees.

I hope the above steps were helpful.

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Good luck in your studies!

Respectfully,
Dr J

Answer by mangeshpjoshi(15) About Me  (Show Source):
You can put this solution on YOUR website!
dear student,
let first angle is x degree and second(as given instruction)=4x and third angle= 2x+5
so now we know addition of 3 angles of a triangle is 180 degree so
making addition of above angles
x+4x+(2x+5)=180 degree
x+4x+2x+5= 180degree
7x+5=180 degree
7x= 180-5
7x=175
x=175/7
so x= first angle= 25 degree
second =4x=100 degree
and third 2x+5= 55 degree
thanks
faithfully
mangesh joshi