Answer:
<em>y = - cos ( </em><em> x + </em>
<em> ) </em>
Step-by-step explanation:
y = A cos ( Bx + C) + D
Vertical shift D = 0
A = - 1
Compression / Stretching B
Period of given function is
Period of cos x is 2π
=
⇒ B =
Horizontal shift is C ÷ B
Horizontal shift of given function is
= C ÷
⇒ C =
So, the equation of given function is
<em>y = - cos ( </em><em> x + </em>
<em> ) </em>
Answer:
It will take Rosa 5 and a half (5.5) weeks to have the same amount of money in both accounts.
Step-by-step explanation:
For this problem, we will have to set two expressions equal to each other. The first expression will represent Rosa's saving account, which already has $117 in it. Every week (), she adds $21 to her savings account:
The second expression will represent Rosa's checking account. Rosa's checking account already has $95 in it. Every week (), she adds $25 to her checking account:
Now that we have our two expressions, set them equal to each other. This is our equation that will be used to find the number of weeks () it takes until Rosha has the same amount of money in both accounts:
Subtract from both sides of the equation:
Subtract from both sides of the equation:
Divide both sides of the equation by the coefficient of , which is
:
So it will take five and a half weeks for her accounts to have the same amount of money.
_
Check your work by substituting into the initial equation:
Since the accounts have the same amount, the answer is correct!