SOLUTION: In triangle ABC, a=15cm, b=21cm, and m∠C=90 degree. Solve the triangle. Can someone help me with this? Thank you.

Algebra.Com
Question 1077715: In triangle ABC, a=15cm, b=21cm, and m∠C=90 degree. Solve the triangle.
Can someone help me with this?
Thank you.
Found 4 solutions by Boreal, MathLover1, MathTherapy, Alan3354:
Answer by Boreal(15235)   (Show Source): You can put this solution on YOUR website!
This is a right triangle with legs 15 and 21. The hypotenuse or c, is sqrt (225+441)=sqrt(666)=25.81.
can use Law of Sines
25.81/sin C=25.81= a/sin A=15/sin A; sin A=15/25.81=0.5812. Take the arc sin (0.5812)=35.53 deg angle A
21/25.81=0.8136; arc sin (0.8136)=54.45 deg angle B
Answer by MathLover1(20850)   (Show Source): You can put this solution on YOUR website!

In triangle , , , and < degree.
use Law of Cosines:



......






















°

Answer by MathTherapy(10555)   (Show Source): You can put this solution on YOUR website!
In triangle ABC, a=15cm, b=21cm, and m∠C=90 degree. Solve the triangle.
Can someone help me with this?
Thank you.
This is a right triangle, so for the missing side c, we get: 

To get the smaller angle (A), calculate: 

To get ∡B, just subtract ∡A from 90o.

Why do the other people who responded make this problem look so complex?

Why would anyone want to use the law of cosines and/or the law of sines? Unless, of course, it is so requested? 

Answer by Alan3354(69443)   (Show Source): You can put this solution on YOUR website!
 In triangle ABC, a=15cm, b=21cm, and m∠C=90 degree. Solve the triangle.

-----------

It's a right triangle, so c^2 = a^2 + b^2

======================

sin(A) = a/c

sin(B) = b/c

 

RELATED QUESTIONS


Triangle ABC has an exterior angle, ∠DAB, and two remote inner angles, ∠B and  (answered by ankor@dixie-net.com)

in triangle abc m∠a= x^2 m∠b= 11x+5 and m∠c= 13x-17 what is the longest  (answered by Edwin McCravy)

Hi!

7.   If AB < AC < CB in ΔABC, then which of the following is true?  (1 point)
 (answered by josgarithmetic)

In a triangle abc,|ac|=16cm,|bc|=10cm, ∠bac=30 degrees. If ∠abc = 90 degrees,  (answered by ewatrrr)

In ΔABC, m∠A = 3x + 40, m∠B = 8x + 35, and m∠C = 10x. Which is the  (answered by richwmiller)

I need help with this problem. Thank you.

Use a calculator. Unless otherwise... (answered by Fombitz)

In ∆ABC, m∠A = 3x + 1, m∠B = 4x - 17,and m∠C = 5x - 20. Which... (answered by Fombitz)

In triangle ABC, m∠A=53° and m∠B=84°.... (answered by ikleyn)

In ΔABC, m∠C = 118 and m∠B = 44. Which is the shortest side of the... (answered by vleith)