Phone card = $20
You need to minus 17.92 from 20 = $2.08
$2.08 / 0.13 = how many minutes
= 16
X^2+2x^2=14+7
3x^2=21
x^2=7
x=±√7
I assume your question amounts to finding the period of f(t)=8sin(4 pi t). A period L is a positive number such that f(t+L)=f(t) for all t. Since sin(x) is 2 pi perodic we can find the least number L such that 4pi(t+L)=4*pi*t+2*pi. Multiplying out we get
4pi(t+L)=4*pi*t+4*pi*L and we want to find L such that we get 4*pi*t+2*pi, notice if we take L=1/2 we get the desiered result 4*pi*t+4*pi*1/2=4*pi*t+2*pi. This proves that L=1/2 and your function has a period of 1/2.
The correct answer is a 360
I'm assuming you're talking about the area of a square, which is
².
Plug in the radius, 26 cm, for r.
² <<equation
If you want the answer,
² =
2,123.7 cm²
