Answer:
[tex]120\ cm^2[/tex]
Step-by-step explanation:
The area [tex](A_t)[/tex] of a triangle is equal to half the product of its length (L) because of its height (h).
[tex]A_t = 0.5h*L[/tex]
The base of the triangles is [tex]L = 4\ cm[/tex]
The height of the triangles is [tex]h = 5\ cm[/tex]
Then the area of one of the triangles is:
[tex]A_t = 0.5(4)(5)\\A_t = 10\ cm^2[/tex]
The figure is formed by 12 equal triangles, then the area of the figure [tex](A_f)[/tex] is:
[tex]A_f = 12(A_t)\\A_f = 12(10)\\A_f = 120\ cm^2[/tex]
