SOLUTION: PLEASE HELP! I have no idea how to solve for x in matrices [-14 -19 18]-([-4 1x 0] -[16 12 -8])=[6 5 10] A.x = -7 B.x = 6 C.x = 4 D.x = -2 E. x = -4 F. x = -3

Algebra ->  Matrices-and-determiminant -> SOLUTION: PLEASE HELP! I have no idea how to solve for x in matrices [-14 -19 18]-([-4 1x 0] -[16 12 -8])=[6 5 10] A.x = -7 B.x = 6 C.x = 4 D.x = -2 E. x = -4 F. x = -3       Log On


   

Question 982307: PLEASE HELP! I have no idea how to solve for x in matrices
[-14 -19 18]-([-4 1x 0] -[16 12 -8])=[6 5 10]
A.x = -7
B.x = 6
C.x = 4
D.x = -2
E. x = -4
F. x = -3

Found 2 solutions by solver91311, KMST:
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


What would x have to be so that the given sum of matrices is correct.

When you add matrices, you sum the corresponding elements, so for the given sum of matrices to be correct, x must make the following equation true.



Unfortunately none of your choices fit this description, and at least according to what I understand the rules of addition to be, the last element of the sum matrix is incorrect as well. Check your typing.

John

My calculator said it, I believe it, that settles it

Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
Adding matrices is just like adding numbers.
Your matrices have 1 row with 3 elements (numbers) on each row.
You work with the first number on the matrices to the left of the equal sign
to get the first number in the result matrix to the right of the equal sign,
-14-(-4-16) = -14-(-20) = -14+20 = 6 ,
but that was already done for you.
You would work with the last(third) number on the matrices to the left of the equal sign
to get the last number in the result matrix to the right of the equal sign,
18-(0-8) = 18-(0-(-8)) = 18-8 = 10 ,
but that was already done for you.
The same calculation with the middle number is
-19-%281x-12%29+=+5
We can try to solve that for 1x ,
and then figure out what was meant by 1x.
Normally you would say that 1x means 1 times x ,
and you would write it as just x .
Another interpretation is that what was meant by 1x was
a two digit number with 1 as the tens digit and x as the units digit.
-19-%281x-12%29+=+5
-%281x-12%29+=+5%2B19
-1x%2B12+=+24
-1x+=+24-12
-1x+=+12
1x=-12
Normally you would say that 1x means 1 times x ,
and you would write it as just x .
Another interpretation is that what was meant by 1x was
a two digit number with 1 as the tens digit and x as the units digit.
Neither interpretation works for any of the options given.
Maybe there was a typo in the problem as given to you.