Answer: The answer is 381.85 feet.
Step-by-step explanation: Given that a window is 20 feet above the ground. From there, the angle of elevation to the top of a building across the street is 78°, and the angle of depression to the base of the same building is 15°. We are to calculate the height of the building across the street.
This situation is framed very nicely in the attached figure, where
BG = 20 feet, ∠AWB = 78°, ∠WAB = WBG = 15° and AH = height of the bulding across the street = ?
From the right-angled triangle WGB, we have

and from the right-angled triangle WAB, we have'

Therefore, AH = AB + BH = h + GB = 361.85+20 = 381.85 feet.
Thus, the height of the building across the street is 381.85 feet.
4.2 is the answer of this question you are asking ✌️
Answer:
The numbers are 20 and 140
Step-by-step explanation:
<u><em>The question in English is</em></u>
Find 2 numbers knowing that the second number is 7 times greater than the first, and the sum between the double of the first number and the triple of the second is 460
Define the variables
Let
x ----> the first number
y ----> the second number
we know that
-----> equation A
----> equation B
Solve the system of equations by substitution
Substitute equation A in equation B

solve for x



<em>Find the value of y</em>
---->
The numbers are 20 and 140
$29.99=$30
$30-$15=$15
Ace's profit is $15
Answer:
80
Step-by-step explanation:
500 to 900? = 80.