17.91*21=376.11
i used one side of the triangle because both sides are equal
Answer with explanation:
Two equal angles of Isosceles Triangle =21.21°
Two equal sides of Isosceles Triangle =17.91 feet
Third Angle of Triangle
Using Angle sum property of triangle⇒Which states that sum of three angles of triangle is 180°.
→21°.21'+21°.21'+Third Angle=180°
→42°.42'+Third Angle=180°
→Third Angle=180°-42°.42'
→Third Angle=137°.18'
⇒Area of triangle
[tex]=\frac{ab\times \sin C}{2}\\\\=\frac{17.91 \times 17.91\times \sin137^{\circ}.18' }{2}\\\\=\frac{320.7681 \times 0.68}{2}\\\\=\frac{218.122308}{2}\\\\=109.061154[/tex]
=109.062 Square feet(Approx)
