if (-2 1 x+2 )

(3 x-4 5 ) =25
(0 1 3 )

p/s : all the value above in one bracket ( )

a) find the value of x

b) hence ,find (-2 1 x+2 )^-1
( 3 x-4 5 )
(o 1 3 )

p/s : all the value above in one bracket ( )

1 answer

I assume you meant the determinant

24 x + 3 x^2 + 6 x + 10 - 9x = 25

3 x^2 + 21 x -15 = 0

x^2 + 7 x - 5 = 0

x =-7/2 +/- (1/2) sqrt(69)

What a mess, assume you have a typo.

To invert matrix use
http://matrix.reshish.com/inverse.php