Answer: x + 12 = 3x + -22
12 + x = 3x + -22
Reorder the terms:
12 + x = -22 + 3x
Solving
12 + x = -22 + 3x
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '-3x' to each side of the equation.
12 + x + -3x = -22 + 3x + -3x
Combine like terms: x + -3x = -2x
12 + -2x = -22 + 3x + -3x
Combine like terms: 3x + -3x = 0
12 + -2x = -22 + 0
12 + -2x = -22
Add '-12' to each side of the equation.
12 + -12 + -2x = -22 + -12
Combine like terms: 12 + -12 = 0
0 + -2x = -22 + -12
-2x = -22 + -12
Combine like terms: -22 + -12 = -34
-2x = -34
Divide each side by '-2'.
x = 17
Simplifying
x = 17
2x-y=7
y=2x+3
Substitute (2x+3) in for y in the first equation
2x-(2x+3)=7
2x-2x-3=7
-3=7
Becuase -3 does not equal 7 the answer is no solution
Answer:
That is 74 years.
Step-by-step explanation:
1.5% = 0.015.
The equation for the rate of growth is P = 430,000(1.015)^n where n is the number of years.
Triple the population is 430,000 * 3 = 1,290,000, so:
1,290,000 = 430,000(1.015)^n
(1.015)^n = 1290,000 / 430,000 = 3
Taking logs of both sides:
n log 1.015 = log 3
n = log 3 / log 1.015 = 73.8 years
Answer:
a)
90% confidence interval for the mean grading time of all composition papers.
(12.47981 , 13.52019)
b)
Appropriate inequality
The interval is ( 12.47981 < μ < 13.52019)
Step-by-step explanation:
<u><em>Explanation</em></u>:-
a)
Given sample size 'n' = 40
Mean of the sample = 13 minutes
standard deviation = 2 min
level of significance = 0.10 or 90%
90% confidence interval for the mean grading time of all composition papers.
( 13 - 0.52019 , 13 + 0.52019)
(12.47981 , 13.52019)
b)
The interval is ( 12.47981 < μ < 13.52019)
