From the setup of the problem, the "length of the top of the bookcase, measured along the attic ceiling" will be the hypotenuse of a right triangle, the length "AB". We have both the angle between AB and AC and the length of AC (3.24 meters), so we can use trigonometric identities.
The cosine of the 40 degree angle between AB and AC is equivalent to the length of AC divided by the length of AB. Equivalently, we have:

where "h", the hypotenuse, is the length we want. Rearranging the formula to solve for h we have that

which is 4.2295... meters. Converting to centimeters (multiplying by 100) we have that h = 422.95... centimeters, or if we round the value, h = 423 centimeters.
Quotient is the result of division. Assign a variable to the unknown number. Let's make it x. Write the statement as an equation.
x/5 - 10 = 3
solve for x
x/5 - 10 = 3
x/5 = 3 + 10
x/5 = 13
x = 5 × 13
x = 65
Answer:
True
Step-by-step explanation:
64x³ + 125
64x³ = (4x)³ ← a perfect cube
125 = 5³ ← a perfect cube
Thus 64x³ + 125 ← is a sum of cubes
:
The area.
She is trying to find how to cover it, which would be the area of the floor.
Answer:
even if the first answer is wrong? Just kidding, the first one is -9, second is 0, third is 9, and last is 18
Step-by-step explanation:
-9
0
9
18