Q39 of 54 Page 77

Solve the linear equations x – 2y = 8 and 5x + 3y = 1 by algebraic method.

Equations:


x – 2y = 8 ……eq(i)


5x + 3y = 1 ……eq(ii)


For elimination of one variable from both the equations, multiply the first equation by 5


(x – 2y = 8) ×5 = 5 x – 10 y = 40 ………eq(iii)


Subtracting eq(iii) from eq (ii)


5x + 3y – (5 x – 10 y) = 1 – 40


13 y = - 39


y = - 3


Putting the value of y in equation(i) we get,


x – 2 y = 8


x – 2 × (- 3) = 8


x + 6 = 8


x = 2.


Hence, Solution of the given linear equations are x = 2, y = - 3


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