To solve this we are going to use the formula for the lateral surface area of a regular pyramid:
where
is the lateral surface area.
is the perimeter of the base.
is the slant height.
We know for our problem that
and
, so lets replace those values in our formula and solve for
:
Now we know that the perimeter of the base of our regular triangular pyramid is 33 cm. Remember that the perimeter of a triangle is the sum of its 3 sides. Since our pyramid is regular, its base will be an equilateral triangle, so to f<span>ind the length of the base edge, we just need to divide the perimeter by 3:
</span>
<span>
We can conclude that the length of the base edge of our regular triangular pyramid is
11 cm.</span>
If <u>triangle</u> FGH is <u>equilateral</u>, then all its sides are congruent. The <u>midpoints</u> of the sides are connected to form triangle XYZ. Lines XY, YZ and XZ are middle lines of the triangle FGH.
Triangle midpoint theorem: The line segment connecting the midpoints of two sides of a triangle is parallel to the third side and is congruent to one half of the third side.
According to this theorem, the segment XY is parallel to the side FH and its length is half of FH length.
Therefore, quadrilateral FXYH is trapezoid with two parallel bases XY and FH.
Answer: correct choice is C
Answer:
see explanation
Step-by-step explanation:
Given that U is the midpoint of TV, then
TU = UV , substitute values
8x + 11 = 12x - 1 ( subtract 12x from both sides )
- 4x + 11 = - 1 ( subtract 11 from both sides )
- 4x = - 12 ( divide both sides by - 4 )
x = 3
Thus
TU = 8(3) + 11 = 24 + 11 = 35
UV = 12(3) - 1 = 36 - 1 = 35
Answer:
16 girls
Step-by-step explanation:
boys : girls : total
5 4 5+4 = 9
take the total number of people and divide by 9
36/9 = 4
Each number should be multiplied by 4
boys : girls : total
5*4 4*4 9*4
20 16 36
There are 16 girls