Answer:
40
Step-by-step explanation:
The perimeter of a rectangle is given by the formula,

We substitute,
and

into the above formula to obtain the expression,


We now group the x and y terms on the Left Hand Side of the equation to get.


We now divide through by 2 to get,

Therefore the width of the rectangle is

Draw a diagram to illustrate the problem as shown in the figure below.
Let h the height of the hill. =
At position A, the angle of elevation is 40°, and the horizontal distance to the foot of the hill is x.
By definition,
tan(40°) = h/x h = x tan40 = 0.8391x
(1)
At position B, Joe is (x - 450) ft from the foot of the hill. His angle of elevation is
40 + 18 = 58°.
By definition, tan(58°) = h/(x - 450)
h = (x - 450) tan(58°) = 1.6003(x-450)
h = 1.6003x - 720.135 (2)
Equate (1) and (2).
1.6003x - 720.135 = 0.8391x 0.7612x = 720.135
x = 946.0523
From (1), obtain
h = 0.8391*946.0523 = 793.8 ft
Answer: The height of the hill is approximately 794 ft (nearest integer)
Answer:
<em>It took 31 days for the patch to cover half the lake</em>
<em></em>
Step-by-step explanation:
The patch grows to double its size everyday
the patch completely covers the lake in 32 days
Since the patch doubles itself everyday, this means that the previous day before the 32nd day, the lake was just half covered.
Therefore, the the patch covered half the lake on the 31st day, i.e <em>it took 31 days for the patch to cover half the lake</em>
<em></em>
Answer:
B
Step-by-step explanation:
x is alternate exterior angles and y is 180 - x