The square root of 144 is 12
For there to be 1 car, we consider two possible outcomes:
The first door opened has a car or the second door opened has a car.
P(1 car) = 2/6 x 4/5 + 4/6 x 2/5
P(1 car) = 8/15
For there to be no car in either door
P(no car) = 4/6 x 3/5
P(no car) = 2/5
Probability of at least one car is the sum of the probability of one car and probability of two cars:
P(2 cars) = 2/6 x 1/5
= 1/15
P(1 car) + P(2 cars) = 8/15 + 1/15
= 3/5
Answer:
b
Step-by-step explanation:
Answer:
Step-by-step explanation:
x²+10x+21=0
x²+10x+(10/2)²-(10/2)²+21=0
x²+10x+25-25+21=0
(x+5)²-4=0
(x+5)²=4
(x+y)²=(x+y)(x+y)=x(x+y)+y(x+y)=x²+xy+xy+y²=x²+2xy+y²
(x+y)²=x²+2xy+y²
coefficient of x=2y
y²=[(coefficient of x)/2]²=(2y/2)²=y²