SOLUTION: In △ABC, AC = BC, AB = 6, m∠BAC = 71º. Find the length of the altitude AH.

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Question 1147423: In △ABC, AC = BC, AB = 6, m∠BAC = 71º. Find the length of the altitude
AH.
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39617)   (Show Source): You can put this solution on YOUR website!
.
.
Lower triangle with AB on the bottom

Triangle AHB
AB=6
Angle at A is 19 degree
Angle at B is 71 degree
point H at angle of 90 degree
AH wanted


Answer by ikleyn(52784)   (Show Source): You can put this solution on YOUR website!
.

Given triangle ABC is isosceles; therefore, the altitude AH is the median, at same time.


It means that  AH = BH = 6/2 = 3 units of length.


Then  tan(A) = ,   or


      tan(71°) = ,


which implies  | AH | = 3*tan(71°).      ANSWER

Solved.

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Be aware :   the solution by  @josgarithmetic giving the answer    is   I N C O R R E C T (!)

I came to bring the correct solution.


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