Answer:
240
Step-by-step explanation:
240 times 0.15 (15%) is 36
2(x+7) + x=20
(2)(x) + (2)(7) + x=20 Distribute
2x+14 + x =20
(2x+x) + (14) =20 Combine Like Terms
3x+14=20
- 14 -14 Subtract 14 from both sides
3x = 6
3x/3 6/3 Divide Both Sides by 3
x = 2
Let me know if you still don't understand
Distributing same key numbers
A pyramid is regular if its base is a regular polygon, that is a polygon with equal sides and angle measures.
(and the lateral edges of the pyramid are also equal to each other)
Thus a regular rectangular pyramid is a regular pyramid with a square base, of side length say
x.
The lateral faces are equilateral triangles of side length
x.
The lateral surface area is 72 cm^2, thus the area of one face is 72/4=36/2=18 cm^2.
now we need to find
x. Consider the picture attached, showing one lateral face of the pyramid.
by the Pythagorean theorem:

thus,

thus:

(cm^2)
but

is exactly the base area, since the base is a square of sidelength =
x cm.
So, the total surface area = base area + lateral area =

cm^2
Answer:

cm^2
Answer:
The third book cost $9.03
Step-by-step explanation: