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.
-20 -18 -6 -4 2 4 this is the answer
300/60=5 so your answer is 5 hours
The correct answer is:
[C]: "
" .
____________________________________________________Explanation:____________________________________________________Given:
____________________________________________________ 2 / (9x) = 4 / 7 ; solve for "x" ;
____________________________________________________Cross-multiply:
→ (9x)*4 = 2 * 7 ;
→ 36x = 14 ;
Divide each side of the equation by "36" ;
to isolate "x" on one side of the equation; & to solve for "x" ;
→ 36x / 36 = 14 / 36 ;
x = 14/ 36 ;
→ x = 14/36 = (14÷2) / (36÷2) = 7/18 ;
______________________________________________________
The answer is: "
" ;
→ which is:
Answer choice: [C]: "
" .
______________________________________________________
