Each base angle is an isosceles triangle measures 55 degrees 30 minutes. Each of the congruent sides is 10 centimeters long. Estimate the following problems to the nearest tenth. A. Find the altitude of the triangle. B.what is the length of the base? C.fund the area of the triangle.

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Answers:

55 deg 30 Minutes = 55.5 degrees 

sin = opp/hyp 

sin(55.5) = altitude/10 

Altitude = 10*sin(55.5) 

Altitude = 10 * sin(55.5) = 8.241261886 

Rounded to nearest 10th 

Altitude = 8.2 cm 

b. for base use Low of Cosines 

Let C = base 

Side A and B = length 10 Cm 

c^2 = 2*a^2 -2a^2*cos(<C) 

<C = 180 - 2*55.5 = 180 -111 = 69 degrees 

c = sqrt ( 2a^2 - 2a^2*cos(<C) 

c = sqrt ( 2*100- 200*cos(69)) 

c = sqrt (200 - 200*cos(69) ) = 11.32812474 



Answer base 
c = 11.3 cms 

c. 
Area = (1/2)*b * h 
Area = (1/2)*(answer a * answer b) 
Area = (1/2)* 11.32812474* 8.241261886 = 46.67902132 

Area = 46.7 (rounded) 

Area = ( 1/2) * a*b*sin(<C) = (1/2)*10*10*sin(69) = 
Area = 50* sin(69) = 46.67902132 
Area = 46.7 (rounded)

To solve the problwm we must know about trignometric functions.

Trigonometric functions

[tex]Sin \theta=\dfrac{Perpendicular}{Hypotenuse}[/tex]

[tex]Cos \theta=\dfrac{Base}{Hypotenuse}[/tex]

[tex]Tan \theta=\dfrac{Perpendicular}{Base}[/tex]

where perpendicular is the side of the triangle which is opposite to the angle, and the hypotenuse is the longest side of the triangle which is opposite to the 90° angle.

The area of the triangle is 46.672 cm².

Given to us

  • Base angle, ∠P = ∠R = 55° 30'
  • Each Congruent Side, QP =QR = 10 cm

Assumption

Let the altitude(QS) be h, and the base of the triangle(PR) be b.

A.)   The altitude of the triangle

The altitude of the triangle

In ΔPQS

[tex]Sin(55^o\ 30') = \dfrac{Perpendicular}{Hypotenuse}\\\\Sin(55^o\ 30') = \dfrac{QS}{PQ}\\\\Sin(55^o\ 30') = \dfrac{h}{10}\\\\h = Sin(55^o\ 30') \times 10\\\\h = 8.24[/tex]

Hence, the altitude of the isosceles triangle is 8.24 cm.

B.)  The length of the base

The length of the base

In ΔPQS

[tex]Cos(55^o\ 30') = \dfrac{Base}{Hypotenuse}\\\\Cos(55^o\ 30') = \dfrac{PS}{PQ}\\\\Cos(55^o\ 30') = \dfrac{\dfrac{b}{2}}{10}\\\\\dfrac{b}{2} = cos(55^o\ 30') \times 10\\\\{b} = cos(55^o\ 30') \times 10\times 2\\\\b = 11.33[/tex]

Hence, the base of the isosceles triangle is 11.33 cm.

C.) The area of the triangle

The area of the triangle

[tex]Area\ \triangle = \dfrac{1}{2}\times Height(altitude)\times base[/tex]

[tex]Area\ \triangle PQR = \dfrac{1}{2}\times h\times b[/tex]

                    [tex]= \dfrac{1}{2}\times 8.24\times 11.33\\\\=46.672\ cm^2[/tex]

Hence, the area of the triangle is 46.672 cm².

Learn more about Trignometric functions:

https://brainly.com/question/21286835

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