I need to find x for this geometry question
2 answers:
You might be interested in
Have you learned matrices yet? I'm going to use that to solve these, please refer to the photos.
I solved the system by using a matrix calculation. The work always needs to be shown and you do that by setting up the matrix like in the first photo and also writing out all your equations. In a TI calculator, to do this you press 2ND-X^-1,GO TO EDIT - [A] - 3×4- now enter the coefficient of the system of equations variables. NOW 2ND MODE- 2ND-X^-1 -GO TO MATH- ALPHA APPS
Now, if you don't know this you may be confuse so after rref([A]) was enter a matrix came up with [1 0 0 -21] in the top row this means x equal -21. So, the next row is y and it came out as [0 1 0 46] so y equals 46 and I'm going to let you figure out what z is by looking at the matrix.
SO... X=-21 Y=46 and Z=-10
Let's Test it
I solved the system by using a matrix calculation. The work always needs to be shown and you do that by setting up the matrix like in the first photo and also writing out all your equations. In a TI calculator, to do this you press 2ND-X^-1,GO TO EDIT - [A] - 3×4- now enter the coefficient of the system of equations variables. NOW 2ND MODE- 2ND-X^-1 -GO TO MATH- ALPHA APPS
Now, if you don't know this you may be confuse so after rref([A]) was enter a matrix came up with [1 0 0 -21] in the top row this means x equal -21. So, the next row is y and it came out as [0 1 0 46] so y equals 46 and I'm going to let you figure out what z is by looking at the matrix.
SO... X=-21 Y=46 and Z=-10
Let's Test it
The exponential distribution is:
where
The probability we want is how likely will a dvd player last more than 8 years, given it has already lasted 5 years
To find this, you use conditional probability.
where A is P(x>8) and B is P(x>5)
To find these probabilities, integrate over the distribution:
Sub into conditional probability formula:
Final Answer: Given a dvd player is more than 5 years old, the probability that it will last another 3 more years is about 54.9%
where
The probability we want is how likely will a dvd player last more than 8 years, given it has already lasted 5 years
To find this, you use conditional probability.
where A is P(x>8) and B is P(x>5)
To find these probabilities, integrate over the distribution:
Sub into conditional probability formula:
Final Answer: Given a dvd player is more than 5 years old, the probability that it will last another 3 more years is about 54.9%