You first have to turn 2x + 4y = -8 into y = mx + b before graphing. To do this, you subtract 2x from the left side of the equation because inverse operations. This will bring 2x to the right side. Now, you will have 4 = -2x + 8. However, you cannot have a number with y. Therefore, you must divide -8 and 2 by 4. You will get y = -1/2 x + 2 as your equation.
To graph -1/2x + 2, you must remember rise/run. Since it is NEGATIVE -1/2, your slope will go downwards (1 down, 2 across) starting from y = 2.
49/60 - 3/20 = (49 - 3(3))/60 = (49 - 9)/60 = 40/60 = 4/6 = 2/3
Answer:
2/3
Answer:
1.) .399
2.) {.369, .429}
Step-by-step explanation:
The proportion of criminals in this sample that were caught was 
=.39944, .399 rounded to three decimal places.
To construct the confidence interval, you need three pieces of information: the statistic, the critical value, and the standard error.
The statistic is given in the first part of the problem with the proportion of criminals in the sample that were caught was .399.
The critical value, we are told, is the z equivalent of 90%, or 1.645. You can find this value using a z table or with the inverse normal function on a calculator.
Finally, we need the standard error. The formula for standard error for a proportion with a single population is 
so in this situation it would be 
=.0183.
The confidence interval would be .399±.018×1.645 or .399±.030 {.369, .429}
Answer: the population be after 10 years is 289145
Step-by-step explanation:
The growth rate is exponential. We would apply the formula for exponential growth which is expressed as
y = b(1 + r)^t
Where
y represents the population after t years.
t represents the number of years.
b represents the initial population.
r represents rate of growth.
From the information given,
b = 210000
r = 3.25% = 3.25/100 = 0.0325
t = 10 years
Therefore,
y = 210000(1 + 0.0325)^10
y = 210000(1.0325)^10
y = 289145
Let x represent the number of liters of 50% acid Theresa puts into the mix. The the number of liters of 30% acid will be (420-x). The total amount of acid in the final solution will be ...
0.50x + 0.30(420-x) = 0.45(420)
0.20x + 126 = 189 . . . . . . . . . . . . . . . simplify
0.20x = 63 . . . . . . . . . . . . . . . . . . . . . subtract 126
x = 63/0.20 = 315 . . . . . . . . . . . . . . . liters of 50% solution
(420-x) = 420-315 = 105 . . . . . . . . . liters of 30% solution
Theresa should mix ...
105 liters of 30% solution
315 liters of 50% solution
