A matrix is diagonal if

In other words, you want non-zero elements only when the indices of the row and the column are the same: the first element of the first row must be non zero, the second element of the second row must be non-zero, and so on. All other elements must be zero.
Step-by-step explanation:
first you do 3×1 get your answer and then × it by 2 then your answer you get you × it by 3 what you get - by 2 what you get you - by 1 and you get your answer hope I helped
Dang that’s crazy, send me some pics and you got a deal
Take the -3/5 and add it to 1/30 which would equal 19/30, so x= 19/30