9a-2b=-8.....1
-7a+3b=12.....2
So,
1 equation into 3 and 2 equation into 2.
Then,
18a-6b=-24
-14a+6b=24.
4a=0 a=0 .
Substitute a value in 2 equation.
b=4.
Hope it helped
In this item, we have the mean incubation period of 23 days and the standard deviation is 22 days. We use z-score to determine the unknown in each of the items.
(a) less than 21 days.
z-score = (23 - 21) / 22 = 1/11
This translates to a percentage of 53.6%
(b) z-score for 19 days.
z-score = (23 - 19) / 22 = 2/11
This translates to a percentage of 57.2%.
z-score for 23 days.
z-score = (23 - 23)/ 22 = 0
This translates to a percentage of 50%.
The difference between the two numbers is only 7.2%
(c) z-score of 25.
z-score = (23 - 25)/ 22 = -1/11
This translates to a percentage of 42.3%.
Then, subtract this value from 100 to give us the final answer of 57.2%.
The answer is B. (y = 4)
Further explanation:
–4y + 8 = 4(2y – 2) – 2(–16 + 8y)
= -4y + 8 = 4 * (2y -2) - 2 * (-16 + 8y)
= -4y + 8 = ( 4 * 2y - 4 *2 ) - (2 * -16 - 2 * 8y )
= -4y + 8 = 8y - 8 - ( -32 - 16y)
= -4y + 8 = 8y - 8 + 32 + 16y
Move y’s to the left & numbers to the right
= -4y - 8y - 16y = -8 + 32 - 8
= 12y - 16y = -16 + 32
Y = 16 / 28
Y = 4 = (B choice)
The radius is 1/2 the diameter so 17 inches. In one turn you will go about 44 inches. The circumference.
Slope is 3
3/1
Rise3 and 1 to the right called run