# Express the following equations in matrix form and solve them by method of reduction.x + 3y = 2, 3x + 5y = 4 - Mathematics and Statistics

Sum

Express the following equations in matrix form and solve them by method of reduction.
x + 3y  = 2, 3x + 5y = 4

#### Solution

Matrix form of the given system of equations is

[(1, 3),(3, 5)] [(x),(y)] = [(2),(4)]

This is of the form AX = B,

where A = [(1, 3),(3, 5)], "X" = [(x),(y)] "and B" = [(2),(4)]

Applying R2 → R2 – 3R1, we get

[(1, 3),(0, -4)] [(x),(y)] = [(2),(-2)]

Hence, the original matrix A is reduced to an upper triangular matrix.

∴ [(x + 3y),(0 - 4y)] = [(2),(-2)]
∴ By euality of matrices, we get
x + 3y = 2                  ...(i)
– 4y = – 2                  ...(ii)
From equation (ii),
y = (1)/(2)
Sustituting y = (1)/(2) in equation (i), we get

x + 3/2 = 2

∴ x = 2 - (3)/(2) = (1)/(2)

∴ x = (1)/(2) "and y" =(1)/(2) is the required soution.

Concept: Application of Matrices
Is there an error in this question or solution?
Chapter 2: Matrices - Exercise 2.6 [Page 80]

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