Answer:
Step-by-step explanation:
<u>Funciones Trigonométricas</u>
La identidad principal en trigonometría es:
Si sabemos que A es un ángulo agudo (que mide menos de 90°), su seno y coseno son positivos.
Dado que Sen A = 4/5, calculamos el coseno:
Sustituyendo:
Tomando raíz cuadrada:
La tangente se define como:
Substituyendo:
Answer: Choice A, x=-4
Step-by-step explanation:
1. 9x−(3x+9)=2x−25
2. 9x-3x-9=2x-25
3. 6x-9=2x-25
4. 6x-9=2x-25
-2x -2x
5. 4x-9=-25
+9 +9
6. 4x=-16 (divide both sides by 4)
7. x=-4
let's bear in mind that sin(θ) in this case is positive, that happens only in the I and II Quadrants, where the cosine/adjacent are positive and negative respectively.
![\bf sin(\theta )=\cfrac{\stackrel{opposite}{5}}{\stackrel{hypotenuse}{6}}\qquad \impliedby \textit{let's find the \underline{adjacent side}} \\\\\\ \textit{using the pythagorean theorem} \\\\ c^2=a^2+b^2\implies \pm\sqrt{c^2-b^2}=a \qquad \begin{cases} c=hypotenuse\\ a=adjacent\\ b=opposite\\ \end{cases} \\\\\\ \pm\sqrt{6^2-5^2}=a\implies \pm\sqrt{36-25}\implies \pm \sqrt{11}=a \\\\[-0.35em] ~\dotfill](https://tex.z-dn.net/?f=%5Cbf%20sin%28%5Ctheta%20%29%3D%5Ccfrac%7B%5Cstackrel%7Bopposite%7D%7B5%7D%7D%7B%5Cstackrel%7Bhypotenuse%7D%7B6%7D%7D%5Cqquad%20%5Cimpliedby%20%5Ctextit%7Blet%27s%20find%20the%20%5Cunderline%7Badjacent%20side%7D%7D%20%5C%5C%5C%5C%5C%5C%20%5Ctextit%7Busing%20the%20pythagorean%20theorem%7D%20%5C%5C%5C%5C%20c%5E2%3Da%5E2%2Bb%5E2%5Cimplies%20%5Cpm%5Csqrt%7Bc%5E2-b%5E2%7D%3Da%20%5Cqquad%20%5Cbegin%7Bcases%7D%20c%3Dhypotenuse%5C%5C%20a%3Dadjacent%5C%5C%20b%3Dopposite%5C%5C%20%5Cend%7Bcases%7D%20%5C%5C%5C%5C%5C%5C%20%5Cpm%5Csqrt%7B6%5E2-5%5E2%7D%3Da%5Cimplies%20%5Cpm%5Csqrt%7B36-25%7D%5Cimplies%20%5Cpm%20%5Csqrt%7B11%7D%3Da%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill)
Answer:Theo worked for 10.5 hours.
Kade worked for 16.5 hours
Step-by-step explanation:
10(1/2x + 6) = 8
5x + 60 = 8
5x = 8 - 60
5x = - 52
x = -52/5
