Solve the system of equations
Given System of equations are
Let
∴ Given system of equation becomes
2p + 3q + 10r = 4
4p – 6q + 5r = 1
6p + 9q – 20r = 2
The given System of Equations can be written in the form of AX = B
Here A = and B = , X =
Now we need to find |A|
∴ |A| = = 2 × (120 – 45) – 3 × (- 80 – 30) + 10 × (36 + 36)
= 150 + 330 + 720
= 1200
Since, |A| ≠ 0
∴ A is non-singular. So, it’s inverse exists
Cofactor of an element aij = Aij
A11 = (-1)1+1× 75 = 1 × 75 = 75
A12 = (-1)1+2× (-110) = (-1) × (-110) = 110
A13 = (-1)1+3× 72 = 1 × (72) = 72
A21 = (-1)2+1× (-150) = (-1) × (-150) = 150
A22 = (-1)2+2 × (-100) = 1 × (-100) = -100
A23 = (-1)2+3 × 0 = (-1) × 0 = 0
A31 = (-1)3+1 × 75 = 1 × 75 = 75
A32 = (-1)3+2 × (-30) = (-1) × (-30) = 30
A33 = (-1)3+3 × (-24) = 1 × (-24) = -24
Adj A = =
A-1 = (Adj A)/|A|
A-1 =
Now,
Since, AX = B
∴ X = A-1B
∴ p = �, q = 1/3, r = 1/5
∴ x = 1/p = 2; y = 1/q = 3; z = 1/r = 5
So, x = 2; y = 3; z = 5