Question

[a+b b+c] =[9 -1][2b 2a-3d] =[6 18] determine a, b, c, d

Answer 1

Oi 

(a+b, b+c) = (9, -1)

(2b , 2a-3d) = (6,18)

a + b = 9
b + c = -1

2b = 6
2a - 3d = 18

b = 6/2 = 3

a + 3 = 9
a = 6

2*6 - 3d = 18
3d = 12 - 18 = -6
d = -6/3 = -2

b + c = -1
3 + c = -1
c = -4 

a = 6, b = 3, c = -4, d = -2

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