How do you solve a triangle given A=58 degrees, a=11.4, b=12.8?

1 Answer
May 24, 2018

Case 1 : ˆA58,ˆB=72.2,ˆC=49.8,a=11.4,b=12.8,c=10.27

Case 2 ˆA=58,ˆB=106.8,ˆC=14.2,a=11.4,b=12.8,c=3.3

Explanation:

a=11.4,b=12.8,ˆA=58

Applying Law of Sines,

asinA=bsinB=csinC

sinB=bsinAa

sinB=12.8sin5811.4=0.9522

ˆB=sin10.9522=72.2

Also sin B = sin (180 - B)#

Hence ˆB=18072.2=107.8

ˆC=1805872.2=49.8

Also ˆC=18058107.8=14.2

c=asinCsinA=11.4sin49.8sin58

c=10.27

Also c=11.4sin14.2sin58=3.3

Measurements of triangle are

Case 1 : ˆA58,ˆB=72.2,ˆC=49.8,a=11.4,b=12.8,c=10.27

Case 2 ˆA=58,ˆB=106.8,ˆC=14.2,a=11.4,b=12.8,c=3.3