Devin is making a candle by pouring melted wax into a mold in the shape of a square pyramid. each side of the base of the pyramid is 9cm and the height of the pyramid is 10cm. to get the wax for the candle, devin melts cubes of wax that are each 4cm by 4cm by 4cm. how many of the wax cubes will devin need to make the candle? show work ❤

  5 cubes

Step-by-step explanation:

The volume of a square pyramid is given in terms of its side length (s) and height (h) as ...

  V = (1/3)s^2·h

For the given measurements, the volume is ...

  V = (1/3)(9 cm)^2 ·(10 cm) = 270 cm^3

___

The volume of each cube of wax is the product of its length, width, and height, so is ...

  V = (4 cm)^3 = 64 cm^3

___

Then the number of wax cubes required to fill the pyramid is ...

  (270 cm^3)/(64 cm^3/cube) = 4 7/32 cubes

Four cubes are not quite enough to make the candle.

Devin will need 5 cubes to make the candle.

b

step-by-step explanation:

the solution of the equation is 2.23 ⇒ answer b

step-by-step explanation:

* lets revise the meaning of exponential function

- the form of the exponential function is y = ab^x, where a ≠ 0, b > 0 ,  

  b ≠ 1, and x is any real number

- it has a constant base b

- it has a variable exponent x

- to solve an exponential equation, take the log or ln of both sides,  

  and solve for the variable

* lets solve the problem

∵

- the base is 7 and the exponent is x

- insert ㏑ in both sides

∴

- use the rule

∴ x ㏑(7) = ㏑(77)

- to find x divide both sides by ㏑(7)

∴

* the solution of the equation is 2.23 to the nearest 2 decimal places