Answer:
Step-by-step explanation:
90.9^2 - 21.2^2 = b^2
8,262.81 - 449.44 = b^2
b = 88.39326897450959189749074160142
To find the average speed for the whole race, you just have
to add the speed from a starting marker and the speed from the turnaround
marker going back and divide it by 2 since there are only two speeds involved.
10 m/s + 16m/s = 26 m/s / 2 = 13 m/s
Therefore, the average speed for the whole race is 13 m/s.
Answer:
A and C
Step-by-step explanation:
Given
2cos²x - 2 = 0 ( add 2 to both sides )
2cos²x = 2 ( divide both sides by 2 )
cos²x = 1 ( take the square root of both sides )
cos x = ± 
= ± 1
cos x = 1 ⇒ x = 
(1) = 0°
cos x = - 1 ⇒ x = (- 1) = 180°
If it is a system of two unknowns:
1) 4x-8y=5 multiple by 3
2)6x-12y=10 multiple by -2
then
12x-24y=15
-12x+24y=-20
x and y equals 0, so
Answer: no solution
Answer:
$1000 + $25m and $1300 - 25m ;
1100 + 2.75m
2010 (4th month)
2011 ( 7th month)
Step-by-step explanation:
Joline's account :
Initial deposit = $1000
Monthly deposit = $25
Monthly withdrawal = $25
Number of months = 12
Let m = number of month at any point in time
Initial deposit + total deposit
Amount in Joline's account ; first 12 months
$1000 + $25m - - - (1)
Next 12 months :
$1000 + $25 *12 - 25m
1300 - 25m
Sofia's account :
Deposit amount = $1100
Interest per month = 0.25% = 0.0025
1100 + (1100 * 0.0025 * m)
1100 + 2.75m - - (2)
To find the month:
Equate equation 1 and 2, then find m
$1000 + $25m = 1100 + (1100*0.0025*m)
1000 + 25m = 1100 + 2.75m
25m - 2.75m = 1100 - 1000
22.25m = 100
m = 100 / 22.25
m = 4.494
In year 2010, they have approximately the same amount in the fourth month
1300 - 25m = 1100 + 2.75m
1300 - 1100 = 2.75m + 25m
200 = 27.75m
m = 200 / 27.75
m = 7.207
In 2011 ; they have approximately the se amount in the 7th month
