Answer:
x = - 1 ± 2i
Step-by-step explanation:
we can use the discriminant b² - 4ac to determine the nature of the roots
• If b² - 4ac > , roots are real and distinct
• If b² - 4ac = 0, roots are real and equal
• If b² - ac < 0, roots are not real
for x² + 2x + 5 = 0
with a = 1, b = 2 and c = 5, then
b² - 4ac = 2² - (4 × 1 × 5 ) = 4 - 20 = - 16
since b² - 4ac < 0 there are 2 complex roots
using the quadratic formula to calculate the roots
x = ( - 2 ± 
) / 2
= (- 2 ± 4i ) / 2 = - 1 ± 2i
I've done the first four questions. Use this method to answer the rest. For an odd number of objects find the cost of one and multiply by how many you are asked to find.
Since this is a percentage, all you have to do is divide 21 from 80 and multiply that by 100
21/80 = .2625 * 100 is 26.25
The answer closest to this is 25%, so the answer is 25%
Hope this helped! :D
Answer:
<h3>0.1</h3>
Step-by-step explanation:
Probability = expected outcome/total outcome
If a bag contains 3 red balls, 8 blue balls and 11 white balls, then the total outcome will be;
Total outcome = 3 + 8 + 11 = 22 balls
Since we are drawing two balls with replacement;
Probability of drawing red ball = number of red/total outcome = 3/22
Probability of drawing white ball = number of while/total outcome = 11/22 = 1/2
Probability of drawing red first and then white = 3/22 * 1/2
Probability of drawing red first and then white = 3/44
To the nearest tenth, 3/44= 0.1
In percent = 6.8%
Given:
Ten People
5 people = 30 years old
3 people = 32 years old
1 person = 31 years old
1 person = 65 years old
We need to arrange the ages in order from least to greatest.
30, 30, 30, 30, 30, 31, 32, 32, 32, 65
65 is the outlier.
A.) mean age without the outlier. count of the numbers : 9
5 x 30 = 150
1 x 31 = 31
3 x 32 =<u> 96</u>
total age 277
÷ # of pax<u> 9</u>
mean 30.77 round to the nearest tenth 30.80
b.) Standard deviation:
We need to calculate variance first:
5 pax : 30 - 30.80 = - 0.80 ⇒ -0.80² = 0.64 * 5pax = 3.20
1 pax : 31 - 30.80 = 0.20 ⇒ 0.20² = 0.04 * 1pax = 0.04
3 pax : 32 - 30.80 = 1.20 ⇒ 1.20² = 1.44 * 3 pax = 4.32
Variance : (3.20 + 0.04 + 4.32) / 9 pax = 7.56 / 9 = 0.84
Standard deviation is simply the square root of the variance.
Standard deviation = √0.84 = 0.916
0.916 round to nearest hundredths is 0.92
0.916 round to nearest tenths is 0.90
