Answer:
l = 2, m = - 1, n = - 6
Step-by-step explanation:
A scalar matrix has its diagonal elements equal and all other elements zero, so
2l - 4 = 0 ( add 4 to both sides )
2l = 4 ( divide both sides by 2 )
l = 2
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3l + n = 0
3(2) + n = 0
6 + n = 0 ( subtract 6 from both sides )
n = - 6
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3m - n = 3
3m - (- 6) = 3
3m + 6 = 3 ( subtract 6 from both sides )
3m = - 3 ( divide both sides by m )
m = - 1
