Question

in matrics you show that

Answer 1

by applying R1= R1+R2+R3
x+2a x+2a x+2a
a x a
a a x

take x+2a as common
(x+2a ) 1 1 1
a x a
a a x
operating c1= c1-c2, c2= c2-c3
(x+2a) 0. 0. 1
a-x x-a a
0 a-x x
then take x-a from c1 and c2 separately