Two corners of a triangle have angles of ( pi )/ 2 π2 and ( pi ) / 6 π6. If one side of the triangle has a length of 14 14, what is the longest possible perimeter of the triangle?

1 Answer
May 12, 2018

color(green)("Longest Possible Perimeter" = 14 + 24.25 + 28 = 66.25 " units"Longest Possible Perimeter=14+24.25+28=66.25 units

Explanation:

hat A = pi/2, hat B = pi/6, hat C = pi - pi/2 - pi/6 = pi/3ˆA=π2,ˆB=π6,ˆC=ππ2π6=π3

To get the longest perimeter, side 14 should correspond to the least angle pi/6π6

Applying Law of Sines,

a / sin A = b / sin B = c / sin CasinA=bsinB=csinC

14 / sin (pi/6) = c / sin (pi/3)14sin(π6)=csin(π3)

c = (14 * sin (pi/3)) / sin (pi/6) = 24.25c=14sin(π3)sin(π6)=24.25

a = (14 * sin(pi/2)) / sin (pi/6) = 28a=14sin(π2)sin(π6)=28

color(green)(" Perimeter " P = a = b + c Perimeter P=a=b+c

color(green)("Longest Possible Perimeter" = 14 + 24.25 + 28 = 66.25 " units"Longest Possible Perimeter=14+24.25+28=66.25 units