How do you solve the triangle given m∠A = 70°, c = 26, a = 25?

1 Answer
Nov 13, 2017

See below.

Explanation:

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From the information given, we can solve this using the Sine Rule:

The sine rule states that:

#sinA/a=sinB/b=sinC/c#

Finding angle C. Since we know angle A and side a, we will use:

#sinA/a=sinC/c#

#sin(70^o)/25=sinC/26=>sinC=(26sin(70^o))/25=0.9778#

#C=sin^-1(sinC)=sin^-1(0.9778)=color(blue)(77.76^o)#

Angle #B = 180^o-(70^o +77.76^o)=color(blue)(32.24^o)#

Side b:

#sin(70^o)/25=sin(32.24^o)/b=>b=(25sin(32.24^o))/sin(70^o)=color(blue)(14.19)#

So the solution is:

#A=70^o#

#B=32.24^o#

#C=77.76^o#

#a=25#

#b=14.19#

#c=26#