1.

Find X and Y, if(i) `X+Y=[[7, 0],[ 2, 5]]`and `X-Y=[[3, 0],[ 0 ,3]]`(ii) `2X+3Y=[[2, 3],[ 4, 0]]`and `3X+2Y=[[2,-2],[-1, 5]]`

Answer» (i) `X+Y = [[7,0],[2,5]]->(1)`
`X-Y = [[3,0],[0,3]]->(2)`
Adding (1) and (2),
`=> 2X = [[10,0],[2,8]]`
`=>X = [[5,0],[1,4]]`
`:. Y = [[7,0],[2,5]] - [[5,0],[1,4]]`
`=> y = [[2,0],[1,1]]`

(ii) `2X+3Y = [[2,3],[4,0]]->(1)`
`3X+2Y = [[2,-2],[-1,5]] ->(2)`
Multiplying (1) by `3` and (2) by `2` and then subtracting,
`6X+9Y-6X-4Y = [[6,9],[12,0]] - [[4,-4],[-2,10]]`
`=>5Y = [[2,13],[14,-10]] `
`=>Y = [[2/5,13/5],[14/5,-2]] `
Now, `3X+2Y = [[2,-2],[-1,5]]`
`=>X = 1/3([[2,-2],[-1,5]] - 2 [[2/5,13/5],[14/5,-2]])`
`=X = 1/3[[6/5,-36/5],[-33/5,12]]`
`=X = [[2/5,-12/5],[-11/5,4]].`


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