The equation for the equation of a triangle is [tex]A = \frac{1}{2} bh[/tex], where A = area of triangle, b = base of triangle, h = height of the triangle.
The altitude is the same as the height of the triangle. That means h = 12. We are also told that the base, b = 15. Plug these numbers into the equation and find A, the area of the triangle:
[tex]A = \frac{1}{2} bh\\
A = \frac{1}{2} (15)(12)\\
A = \frac{1}{2} (180)\\
A = 90 m^{2} [/tex]
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Answer: C) [tex] 90 m^{2} [/tex]