Answer:
Step-by-step explanation:
The formula for arc length in terms of degrees is
and we have everything we need to fill in to find the angle measure.
which is the same as
and
and
so
θ = 253°
We know that
[lateral surface area of a regular triangular pyramid]=3*[area of one <span>equilateral triangle]
so
[area of one </span>equilateral triangle]=lateral surface/3-----> 81/3-----> 27 ft²
[<span>surface area of the regular triangular pyramid]=lateral area+area of the base
area of the base is equals to the area of the lateral sides because are </span>equilateral triangles
therefore
area of the base=27 ft²
[surface area of the regular triangular pyramid]=81+27----> 108 ft²
the answer is
<span>the surface area of the regular triangular pyramid is 108 ft</span>²
Answer:
52/3
Step-by-step explanation:
Use basic Thales therom,
Cross multiply,
3*(5x-8)=4*(3x+7)
3*5x - 3*8 = 4*3x + 4*7
15x - 24 = 12x +28
Add 24 to both sides
15x = 12x + 28 + 24
15x = 12x + 52
Subtract 12x from both sides
15x-12x =52
3x = 52
Divide both sides by 3
x = 52/3