Answer:
156.6 m²
Step-by-step explanation:
To find the surface area of this pyramid, we need to find the area of the base and the sides.
The base triangle has a length of 9 and a height of 7.8. So:
[tex]\frac{bh}{2} = \frac{9\cdot7.8}{2} = \frac{70.2}{2} = 35.1[/tex]
Now, the length of the sides are 9 and the height is 9. So:
[tex]\frac{9\cdot9}{2} = \frac{81}{2} = 40.5[/tex]
Since there are 3 identical sides:
[tex]40.5\cdot3=121.5[/tex]
Add the values:
[tex]121.5+35.1=156.6[/tex]
Hope this helped!
