"Let's consider the diagram"Let's consider the diagram
"I have mentioned"I have mentioned (5pi)/85π8 "as"as 112.5^circ112.5∘
"We can find the area of a triangle given the length of two sides"We can find the area of a triangle given the length of two sides
"and the angle between them using this formula"and the angle between them using this formula
color(blue)(color(blue)("Area"Areacolor(blue)(=1/2*"=12⋅color(blue)("A"Acolor(blue)(*⋅color(blue)("B"B"color(blue)(*sin(c)⋅sin(c)
rarr1/2*8*3*sin(112.5)→12⋅8⋅3⋅sin(112.5)
rarr1/cancel2^1*cancel24^12*sin(112.5)
rarr12*sin(112.5)
rarr12*0.92
color(green)(rArr11.09