Step-by-step explanation:
1. P(pen then pencil) = 15/25 × 10/25 = 3/5 × 2/5 = 6/25
2. P(pen then pencil) + P(pencil then pen) = 6/25 + 6/25 = 12/25
3. P(pencil then pencil) = 10/25 × 10/25 = 2/5 × 2/5 = 4/25
4. P(at least 1 pen) = 1 − P(no pen) = 1 − 4/25 = 21/25
I'm going to use m for minutes
Cell carrier 1
0.15 per minute (0.15m)
$26.50 first, and then add on for every minute
cost carrier 1 = 0.15m + 26.50
carrier 2
0.25 per minute (0.25m)
$14.50 first, and then add on for every minute.
cost carrier 2 = 0.25m + 14.50
to find out when they cost the same, make the two costs equal to each other:
0.15m + 26.50 = 0.25m + 14.50
all that's left is to solve for m
0.15m + 26.50 = 0.25m + 14.50
subtract both sides by 0.15 m
26.50 = 0.2m + 14.50
subtract both sides by 14.50
12 = 0.1 m
divide both sides by 0.1
m = 120
the phone carriers will have the same cost at 120 minutes
So to find the discriminant of a quadratic equation, the formula is b² - 4ac with a = x² coefficient, b = x coefficient, and c = constant. In this case, our equation is 
Firstly, solve the multiplications and the exponents: 
Next, subtract and we find that our discriminant is 0.
*Additional Info: Since the discriminant is zero, this means that this quadratic equation has 1 real solution.
Answer:
I mean I think they are all quadrilateral, but the one that is congruent and perpendicular on both sides is a square.
Step-by-step explanation:
Answer:
Any number multiplied by 2 is even, therefore 2(2n + 16) is even.
If 2(2n + 16) is even, then adding 1 to this makes it odd.
Thus proving that the given expression is an odd number for all 
