Answer:
Step-by-step explanation:
3 times 12 equal 36.
36 minus 15 equals 21.
So Joaquin uses 21 light bulbs.
Answer:
9.405
Step-by-step explanation:
It has become somewhat fashionable to have students derive the Quadratic Formula themselves; this is done by completing the square for the generic quadratic equation ax2 + bx + c = 0. While I can understand the impulse (showing students how the Formula was invented, and thereby providing a concrete example of the usefulness of abstract symbolic manipulation), the computations involved are often a bit beyond the average student at this point.
Use the Pythagorean theorem to find the diameter:
Diameter = √(19.3^2 - 9.5^2)
Diameter = √(372.49 - 90.25)
Diameter = √282.24
Diameter = 16.8 m
Volume of a cylinder = PI x r^2 x h
r = 1/2 diameter = 16.8 /2 = 8.4
h = 9.5 m
Volume = PI x 8.4^2 x 9.5
= PI x 70.56 x 9.5
= PI x 670.32
In terms of PI volume = 670.32PI
As a decimal:
670.32 x 3.14 = 2104.8048 = 2100m^3 ( rounded to the nearest hundred)
