X-intercept appears at when y = 0
So when cos(0.5x) = 0 -> 0.5x = pi/2 + n*pi, where n is any random integers
So x = pi + 2npi, so the angle can be pi, 3pi, 5pi, so on
I think it would be an experiment, correlation does not imply causation, and a case study would be a detailed observation on an individual, I don't know about an observation
Answer:
7th week
Step-by-step explanation:
Let us represent the number of weeks as x
Jill begins the summer with $500 in her savings account. Each week, she withdraws $20.
$500 - $20× x
500 - 20x
Her brother, Sam,starts the summer with $150 in his account. He adds $30 to his account each week.
$150 + $30 × x
150 + 30x
At what week will both Jill and Sam have the same amount in their account?
We solve this be Equating both Equations together
Jill = Sam
500 - 20x = 150 + 30x
Collect like terms
500 - 150 = 30x + 20x
350 = 50x
Divide both sides by 50
50x/50 = 350/50
x = 7 weeks
Therefore, at the 7 week, Jill and sam would have the same amount in their accounts