if triangle ABC is a right triangle and BC is a semicircle, find the total area of the figure below. what is the diameter of the semi-circle? _____ units.
Area=____ units squared (rounded to the nearest hundredth. )
side AB is 3 units long.
Side AC is 4 units long.

Respuesta :

Area of the semi-circle = 9.8125 square units

Solution:

Given ABC is a right triangle.

BC is a semi-circle.

∠BAC = 90°.

AB = 3 units and AC = 4 units.

BC is the hypotenuse of the right triangle ABC.

Using Pythagoras theorem,

In right triangle, square of the hypotenuse is equal to the sum of the squares of the other two sides.

[tex]BC^2=AB^2+AC^2[/tex]

[tex]BC^2=3^2+4^2[/tex]

[tex]BC^2=25[/tex]

Take square root on both sides.

BC = 5 units

The diameter of the semi-circle is 5 units.

Radius = 5 ÷ 2 = 2.5 units

Area of the semi-circle = [tex]\frac{1}{2}\pi r^2[/tex]

                                      [tex]=\frac{1}{2}\times 3.14\times 2.5^2[/tex]

                                      = 9.8125 square units

Area of the semi-circle = 9.8125 square units