4b²+20b+25=0
Divide everything by 4
b²+5b+ 6.25=0
use the quadratic formula
x= (-b+ or - √b²-4ac) /2a
x= (-5 + or - √5²-4*1*6.25) /2(1)
x= -5/2 so
in this case, b= -5/2
Answer:
62.5 mph
Step-by-step explanation:
Given that :
Peter :
Speed = 50mph
Start Time = 9 a. M
Emily :
Start time = 9:30
Speed = x
In other to catch up at 11:30 :
Peter (11:30 - 9:00) = 2hours 30 minutes = 2.5 hrs
Total distance moved by Peter :
Speed * time = 50 * 2.5 = 125miles
For Emily to cover 125 miles in (11:30 - 9:30) = 2 hours
Speed = distance / time
Speed = 125 miles / 2 hours
Speed = 62.5 miles per hour
Answer:
Acute angles are less than 90
obtuse is more than 90
right angles are exactly 90
Step-by-step explanation:
Yes I love this problem so good
The confidence interval formula is computed by:
Xbar ± Z s/ sqrt (n)
Where:
Xbar is the mean
Z is the z value
S is the standard deviation
N is the number of samples
So our given are:
90% confidence interval with a z value of 1.645
Sample size 40, 45
Mean 180, 179
Standard deviation 2, 4
So plugging that information in the data will give us a
confidence interval:
For 1:
Xbar ± Z s/ sqrt (n)
= 180 ± 1.645 (2 / sqrt (40))
= 180 ± 1.645 (0.316227766)
= 180 ± 0.520194675
= 179.48, 180.52
For 2:
Xbar ± Z s/ sqrt (n)
= 179 ± 1.645 (4 / sqrt (45))
<span>= 179 ± 1.645 (0.596284794)</span>
therefore, the answer is letter b
