Triangle

Plane coordinates of vertices: K[19, -4] L[9, 13] M[-20, 8] give Triangle KLM.

Calculate its area and its interior angles.

Correct answer:

S =  271.5
K =  42.4317 °
L =  110.6831 °
M =  26.8851 °

Step-by-step explanation:

x0=19 y0=4  x1=9 y1=13  x2=20 y2=8   LM = ML = (k0,k1) k0=x2x1=(20)9=29 k1=y2y1=813=5   KM = MK = (l0,l1) l0=x2x0=(20)19=39 l1=y2y0=8(4)=12   LK = KL = (m0,m1) m0=x0x1=199=10 m1=y0y1=(4)13=17  k=k02+k12=(29)2+(5)2=86629.4279 l=l02+l12=(39)2+122=3 18540.8044 m=m02+m12=102+(17)2=38919.7231  s=2k+l+m=229.4279+40.8044+19.723144.9777 S=s (sk) (sl) (sm)=44.9777 (44.977729.4279) (44.977740.8044) (44.977719.7231)=2543=27121=271.5
K = angle(KL, KM) K1=arccos(l ml0 m0l1 m1)=arccos(40.8044 19.7231(39) 1012 (17))0.7406 K=K1  °=K1 π180   °=0.7406 π180   °=42.432  °=42.4317=42°2554"
L = angle(LK, LM) L1=arccos(k mk0 m0+k1 m1)=arccos(29.4279 19.7231(29) 10+(5) (17))1.9318 L=L1  °=L1 π180   °=1.9318 π180   °=110.683  °=110.6831=110°4059"
M1=arccos(k lk0 l0+k1 l1)=arccos(29.4279 40.8044(29) (39)+(5) 12)0.4692 M=M1  °=M1 π180   °=0.4692 π180   °=26.885  °=26.8851=26°537"

Try calculation via our triangle calculator.




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Showing 5 comments:
Math student
It's Great!. Am grateful.

6 years ago  1 Like
Math student
Still don't get it though

5 years ago  1 Like
Math student
I find it hard ... But I think I will get there. ... Slowly but surely ...

Math student
I still dont understand

Math student
I need one question





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