To calculate this you need to imagine triangle which points are:
boat
Top of lighthouse
Bottom of lighthouse
That triangle has 90 degrees angle at bottom of lighthouse. That means that we can use trigonometry to determine length between boat and bottom of lighthouse
tan(25) = 89/x
x = 89/tan(25)
x = 190.86
after rounding, the answer is D, 191 feet
Answer:

Step-by-step explanation:


Let's solve for
in the first equation and then solve for
in the second equation.
I will then use the following identity to get right of the parameter,
:
(Pythagorean Identity).
Let's begin with
.
Subtract 2 on both sides:

Divide both sides by -3:

Now time for the second equation,
.
Subtract 1 on both sides:

Divide both sides by 4:

Now let's plug it into our Pythagorean Identity:




The answer to that would be 3/8
The perimeter of a rectangle is twice the sum of its side lengths.
P=2(L+W), we are told that L=3W and P=176 so
2(3W+W)=176
2(4W)=176
8W=176
W=22 ft, since L=3W
L=66 ft
So the yard is 22 feet wide and 66 feet long.
F (x) = 4x ⇒ y = 4x
↓
x = 4y Divide by 4 on both sides
↓
x / 4 = y ⇒ Inverse function = x / 4