Let's say the larger number is x. that means that the smaller number is x - 3. since you know their sum is x + x - 3, and that is equal to 14. so you have the equation x + x - 3 = 14. combine like terms (x) to get 2x - 3 = 14. add three to both sides to get 2x = 17. divide both sides by two to get x = 17/2. so the larger number is 17/2, and the larger number is 11/2 (17/2 - 3 = 11/2)

8 0

3 years ago

Outside temperature over a day can be modeled as a sinusoidal function. Suppose you know the temperature varies between 73 and 9

Naddika [18.5K]

Answer: After about 9.03 hours the temperature first reach 82 degrees.

Step-by-step explanation:

The sinusoidal function is given by :

$y=A\sin[\omega(x-\alpha)]+C$

where, A = amplitude; $\omega=\dfrac{2\pi}{period}$ , α= phase shift on the Y-axis and C = midline.

As per given,

Average daily temperature= $C=\dfrac{73+97}{2}=85$ [midline is average of upper and lower limit.]

A= 97-85 = 12

Phase shift: $\alpha=10$

Period = 24 hours;

$\omega=\dfrac{2\pi}{24}=\dfrac{\pi}{12}$

Substitute all values in sinusoidal function, we get

$y=12\sin[\dfrac{\pi}{12}(x-10)]+85$

Put y= 82, we get

$82=12\sin[\dfrac{\pi}{12}(x-10)]+85\\\\\Rightarrow\ -3= 12\sin[\dfrac{\pi}{12}(x-10)]\\\\=\dfrac{-1}{4}= \sin[\dfrac{\pi}{12}(x-10)]\\\\\Rightarrow\ \dfrac{\pi}{12}(x-10)=\sin^{-1}(\dfrac{-1}{4})\\\\\Rightarrow\ x-10=\dfrac{12}{\pi}(\sin^{-1}(\dfrac{-1}{4}))\\\\\Rightarrow\ x=\dfrac{12}{\pi}(\sin^{-1}(\dfrac{-1}{4}))+10\\\Rightarrow\ x\approx9.03$

Hence, After about 9.03 hours the temperature first reach 82 degrees.

3 0

3 years ago