Answer:
The equation is given by:

Step-by-step explanation:
Sine function:
Has the following format:

In which A is the amplitude and
is the period.
Suppose you know the temperature is 80 degrees at midnight and the high and low temperature during the day are 89 and 71 degrees
This means that the amplitude of the sinusoidal variation function is 89 - 80 = 80 - 71 = 9. This means that 
During a 24-hour day, which means that the period is 24. So




So the variation is:

Assuming t is the number of hours since midnight, find an equation for the temperature, D, in terms of t.
Initial temperature of 80, so:

Answer:
<h2>x = 6.5 cm</h2>
Step-by-step explanation:
The segment 20.2 cm is the tangent. Therefore x and 20.2cm are perpendicular.
Use the Pythagorean theorem:

We have

Substitute:
<em>use (a + b)² = a² + 2ab + b²</em>
<em>subtract x² from both sides</em>
<em>subtract 216.09 from both sides</em>
<em>divide both sides by 29.4</em>

Answer:
99 minutes, or an hour and 39 minutes.
Step-by-step explanation:
It takes Emma 18 minutes to do 14 pages. That means that we can set up a proportion, where Emma uses 18 minutes to do 14 pages, which is equal to x minutes per page!

14x = 18
7x = 9
x = 9/7
So, each page takes 9/7 minutes for Emma to finish.
She will do 77 pages. 77 * (9/7) = 11 * 9 = 99.
So, it will take Emma 99 minutes, or an hour and 39 minutes, to type and spell check 77 pages.
Hope this helps!
Answer
It’s x= -4 for sure
Answer:
see explanation
Step-by-step explanation:
To find the y- intercept let x = 0 in the function
g(0) = 0 - 0 - 84 = - 84 ← y- intercept
To find the x- intercepts let y = 0, that is
x² - 5x - 84 = 0
To factor the quadratic
Consider the factors of the constant term (- 84) which sum to give the coefficient of the x- term
The factors are - 12 and + 7, since
- 12 × 7 = - 84 and - 12 + 7 = - 5, thus
(x - 12)(x + 7) = 0
Equate each factor to zero and solve for x
x - 12 = 0 ⇒ x = 12
x + 7 = 0 ⇒ x = - 7
x- intercepts are x = - 7 and x = 12