find the value of m .
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Step-by-step explanation:
if the 2 matrices are inverse, then their product must be the identity matrix
1 0
0 1
so,
m×3 + 2×-7 = 1
7×3 + 3×-7 = 0
m×-2 + 2×m = 0
7×-2 + 3×m = 1
that means we have to solve only
3m - 14 = 1
3m = 15
m = 5