Answer:
Total area of square base pyramid is 144 square units.
Step-by-step explanation:
It is given that pyramid has a square base with sides 8 and a slant height of 5.
Total area of square base pyramid is
Where, a is side length of square and l is slant height.
Therefore area of square base pyramid is 144 square units.
Your friend is incorrect because if you divide 21 by 7 you will get 3 if you add 7 to 3 you get 10 therefore your friend is incorrect.
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