The area as a function of the height H is:
[tex]A= 9cm*H[/tex]
We know that for a triangle of base B and height H, the area is given by:
[tex]A = \frac{B*H}{2}[/tex]
In this case, we already know that the base measures 18cm, then the formula for the area as a function of the height H is:
[tex]A= \frac{18cm*H}{2} = 9cm*H[/tex]
If you want to learn more about triangles:
https://brainly.com/question/2217700
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