Answer:
Area = 21.7 cm² (nearest tenth)
Step-by-step explanation:
A 30-60-90 triangle is a special right triangle. The measures of its sides have a special relationship in that they are in proportion:
shortest leg : longest leg : hypotenuse = 1 : √3 : 2
- The side opposite 30° is the shortest leg
- The side opposite 60° is the longest leg and is √3 times the length of the shorter leg.
- The side opposite 90° is the hypotenuse and is twice the length of the shorter leg.
So we can also write the ratio as [tex]x : x\sqrt{3} : 2x[/tex] where [tex]x[/tex] is the shortest side.
From inspection of the diagram, the shortest side is 5 cm
⇒ BC (height) = 5 × √3 = 5√3 cm
Now we have the height, we can calculate the area.
Area of a triangle = 1/2 x base x height
= 1/2 x 5 x 5√3
= 21.7 cm² (nearest tenth)