# Angles ratio

The internal angles of a triangle are in ratio 1:4:5 What kind of triangle is it? (solve internal angles and write down and discuss)

Result

A =  18
B =  72
C =  90

#### Solution:

A+B+C = 180
B = 4A
C = 5A

A+B+C = 180
4A-B = 0
5A-C = 0

A = 18
B = 72
C = 90

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right triangle #### To solve this example are needed these knowledge from mathematics:

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