The easiest thing to do to solve all of these is to use the quadratic equation.
The first number (the one attached to x^2) is equal to a. The second number (the one attached to x) is b. The final number (the one with nothing attached) is c.
Ggggggggggggggggggg 51,359
9514 1404 393
Answer:
400 minutes
Step-by-step explanation:
The cost of the first plan is ...
A = 14 + 0.15m . . . . . . . . where m is the number of minutes used
The cost of the second plan is ...
B = 30 + 0.11m
The costs will be equal when ...
14 +0.15m = 30 +0.11m
0.04m = 16 . . . . . . . . . . . . . subtract 14+0.11m from both sides
m = 400 . . . . . . . . . . . . . . . divide by 0.04
The plans will have the same cost for 400 minutes of calls.
2*pi*r = 56.52 ........................................
r = 56.52/2pi ...........................................
r = 56.52/6.28 ........................................
r = 9..............
the period for one wave is 8π
