-3x + y - 2z = 10 |* -1
3x - y +2z = -10
5x -2y -2z = 12
--------------------------- I add these equations term by term
8x - 3y = 2
-3x + y - 2z =10 ⇒ -3x + y - 2z =10
x -y +z = 23 | *2 2x - 2y + 2z = 46
----------------------------- I add these eq.
-x -y = 56
8x - 3y = 2
-x -y = 56
this is the system after i reduce it ( it has only two variables x and y)
Answer:
$209
Step-by-step explanation:
we know that
The equation of the line in slope intercept form is equal to

where
m is the slope
b is the y-coordinate of the y-intercept (initial value)
Let
x ----> the volume of mulch in cubic yards
y ----> the total cost in dollars
we have that
The slope of the linear equation is

----> flat fee to deliver mulch
The linear equation is

For x=6 yd^3
substitute in the equation and solve for y


The answer is C) 40
You would find this answer by using a formula.
Answer:
37.23% probability that randomly selected homework will require between 8 and 12 minutes to grade
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:

What is the probability that randomly selected homework will require between 8 and 12 minutes to grade?
This is the pvalue of Z when X = 12 subtracted by the pvalue of Z when X = 8. So
X = 12



has a pvalue of 0.4052
X = 8



has a pvalue of 0.0329
0.4052 - 0.0329 = 0.3723
37.23% probability that randomly selected homework will require between 8 and 12 minutes to grade
Answer:
The average price of a gallon of orange increased by $0.03 each month.
Step-by-step explanation:
It is 11 months between October 2013 and September 2014 so the price after 11 months =
f(11) = 6.12 + 0.03(11)
= 6.12 + 0.33
= $6.45.
This is an increase of 0.33 / 11 = 0.03 / month.