They are round
that would be your best answer
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
![\dfrac{WG}{WB}=\tan 15^\circ\\\\\\\Rightarrow \dfrac{20}{b}=\tan 15^\circ\\\\\\\Rightarrow b=\dfrac{20}{\tan 15^\circ},](https://tex.z-dn.net/?f=%5Cdfrac%7BWG%7D%7BWB%7D%3D%5Ctan%2015%5E%5Ccirc%5C%5C%5C%5C%5C%5C%5CRightarrow%20%5Cdfrac%7B20%7D%7Bb%7D%3D%5Ctan%2015%5E%5Ccirc%5C%5C%5C%5C%5C%5C%5CRightarrow%20b%3D%5Cdfrac%7B20%7D%7B%5Ctan%2015%5E%5Ccirc%7D%2C)
and from the right-angled triangle WAB, we have'
![\dfrac{AB}{WB}=\tan 78^\circ\\\\\\\Rightarrow \dfrac{h}{b}=\tan 15^\circ\\\\\\\Rightarrow h=\tan 78^\circ\times\dfrac{20}{\tan 15^\circ}\\\\\\\Rightarrow h=361.85.](https://tex.z-dn.net/?f=%5Cdfrac%7BAB%7D%7BWB%7D%3D%5Ctan%2078%5E%5Ccirc%5C%5C%5C%5C%5C%5C%5CRightarrow%20%5Cdfrac%7Bh%7D%7Bb%7D%3D%5Ctan%2015%5E%5Ccirc%5C%5C%5C%5C%5C%5C%5CRightarrow%20h%3D%5Ctan%2078%5E%5Ccirc%5Ctimes%5Cdfrac%7B20%7D%7B%5Ctan%2015%5E%5Ccirc%7D%5C%5C%5C%5C%5C%5C%5CRightarrow%20h%3D361.85.)
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.
Answer:
3 + 3p
Step-by-step explanation:
since there's no equal sign or no value that it shows all of that added together is equivalent to it's not really equal to anything. However if you're asking what that equation would look like if you simplified it down , then it would be 3 + 3p because you combine the like terms
Answer:
Correct choice is D (In a whole pepperoni pizza are 660 calories, in in a whole ham and pineapple pizza are 580 calories).
Step-by-step explanation:
Let x calories be the number of calories a whole pepperoni pizza contains and y calories be the number of calories a whole ham and pineapple pizza contains.
1. If half a pepperoni pizza plus three fourths of a ham and pineapple pizza contains 765 calories, then
![\dfrac{1}{2}x+\dfrac{3}{4}y=765.](https://tex.z-dn.net/?f=%5Cdfrac%7B1%7D%7B2%7Dx%2B%5Cdfrac%7B3%7D%7B4%7Dy%3D765.)
2. If 1/4 of a pepperoni pizza plus a whole ham and pineapple pizza contains 745 calories. then
![\dfrac{1}{4}x+y=745.](https://tex.z-dn.net/?f=%5Cdfrac%7B1%7D%7B4%7Dx%2By%3D745.)
3. Multiply each equation by 4 and get a system of two equations:
![\left\{\begin{array}{l}2x+3y=3060\\x+4y=2980\end{array}\right.](https://tex.z-dn.net/?f=%5Cleft%5C%7B%5Cbegin%7Barray%7D%7Bl%7D2x%2B3y%3D3060%5C%5Cx%2B4y%3D2980%5Cend%7Barray%7D%5Cright.)
From the second equation
, then
![2(2980-4y)+3y=3060,\\ \\5960-8y+3y=3060,\\ \\-8y+3y=3060-5960,\\ \\-5y=-2900,\\ \\y=580.](https://tex.z-dn.net/?f=2%282980-4y%29%2B3y%3D3060%2C%5C%5C%20%5C%5C5960-8y%2B3y%3D3060%2C%5C%5C%20%5C%5C-8y%2B3y%3D3060-5960%2C%5C%5C%20%5C%5C-5y%3D-2900%2C%5C%5C%20%5C%5Cy%3D580.)
Then
![x=2980-4\cdot 580=2980-2320=660.](https://tex.z-dn.net/?f=x%3D2980-4%5Ccdot%20580%3D2980-2320%3D660.)