A pyramid always have a number of slant triangles equal to the number of the sides of the base.
This means that a pyramid always have the number of face which is one more than the number of sides of the base.
Therefore, given that a pyramid has n number of sides of the base, the expression for the number of faces of the pyramid is given by
number of faces = n + 1.
7x + 4 + 9x = 180
16x = 176
x = 11
9x = 9x11 = 99
7x + 4 = 7(11) + 4 = 77 + 4 = 81
<span>in order to form a rectangular image, each angle needs to be equal 90 degreesn
99 - 9 = 90
81 + 9 = 90
answer
</span><span>B. 9°</span>
Answer:
0.4
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Step-by-step explanation: