can any one solve these(adsbygoogle = window.adsbygoogle || []).push({});

I tried too much to understand them but no way:

1- what values of a makes the system have no solution? one solution? many solutions?

x+2y-3z=4

3x-y+5z=2

4x+y+(a^{2}-14)z=a+2

2- find all unit vectors in the plane determined by u=(3,0,1) , v =(1,-1,1)that are prependicular to the vector w=(1,2,0)

3- express the matrix

0 1 7 8

1 3 3 8

-2 -5 1 -8

in the form A = EFGR where E,F,G are elementary matrices and R is in Row-echelon form

4- show that the line

x=0 , y=t , z=t

a. lies in the plane 6x+4y-4z=0

b. is parallel to and below the plane 5x-3y+3z=1

c. is parallel to and above the plane 6x+2y-2z=3

please I have an exam and tried to solve these problems as I'm studying but no way

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# Homework Help: Any one solve these problems?

Can you offer guidance or do you also need help?

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