Answer:
Never
Never
Never
Step-by-step explanation:
The equations given are
2x1−6x2−4x3 = 6 ....... (1)
−x1+ax2+4x3 = −1 ........(2)
2x1−5x2−2x3 = 9 ..........(3)
the values of a for which the system of linear equations has no solutions
Let first add equation 1 and 2. Also equation 2 and 3. This will result to
X1 + (a X2 - 6X2) - 0 = 5
And
X1 + (aX2-5X2) + 2X3 = 8
Since X2 and X3 can't be cancelled out, we conclude that the value of a is never.
a unique solution,
Let first add equation 1 and 2. Also equation 2 and 3. This will result to
X1 + (a X2 - 6X2) - 0 = 5
And
X1 + (aX2-5X2) + 2X3 = 8
The value of a = never
infinitely many solutions.
Divide equation 1 by 2 we will get
X1 - 3X2 - 2X3 =3
Add the above equation with equation 3. This will result to
3X1 - 8X2 - 4X3 = 12
Everything ought to be the same. Since they're not.
Value of a = never.
(a) Average time to get to school
Average time (minutes) = Summation of the two means = mean time to walk to bus stop + mean time for the bust to get to school = 8+20 = 28 minutes
(b) Standard deviation of the whole trip to school
Standard deviation for the whole trip = Sqrt (Summation of variances)
Variance = Standard deviation ^2
Therefore,
Standard deviation for the whole trip = Sqrt (2^2+4^2) = Sqrt (20) = 4.47 minutes
(c) Probability that it will take more than 30 minutes to get to school
P(x>30) = 1-P(x=30)
Z(x=30) = (mean-30)/SD = (28-30)/4.47 ≈ -0.45
Now, P(x=30) = P(Z=-0.45) = 0.3264
Therefore,
P(X>30) = 1-P(X=30) = 1-0.3264 = 0.6736 = 67.36%
With actual average time to walk to the bus stop being 10 minutes;
(d) Average time to get to school
Actual average time to get to school = 10+20 = 30 minutes
(e) Standard deviation to get to school
Actual standard deviation = Previous standard deviation = 4.47 minutes. This is due to the fact that there are no changes with individual standard deviations.
(f) Probability that it will take more than 30 minutes to get to school
Z(x=30) = (mean - 30)/Sd = (30-30)/4.47 = 0/4.47 = 0
From Z table, P(x=30) = 0.5
And therefore, P(x>30) = 1- P(X=30) = 1- P(Z=0.0) = 1-0.5 = 0.5 = 50%
Answer:
D or 176.71 inches squared.
Step-by-step explanation:
the radius is 7.5. put it in a calculator and you get D.
Answer:
Angle A: 90
Angle B: 48
Angle C: 42
Side length A (Hypotinuse): 23.9
SIde length B (Opposite): 17.8
Side length C (Adjacent): 16
Step-by-step explanation:
https://www.calculator.net/triangle-calculator.html?vc=42&vx=&vy=&va=90&vz=16&vb=&angleunits=d&x=0&y=0
Answer: Dylan weighs 45 pounds while Alan weighs 93 pounds.
