Maths-
General
Easy

Question

Use Substitution to solve each system of equations :
- 3X - Y = 7
X + 2Y = 6

hintHint:

find x by substituting y (in terms of x) in the equation and find y by substituting value of  x in the equations.

The correct answer is: ∴ x= -4 and y =5 is the solution of the given pair of equations.


    Ans :- x = -4; y = 5
    Explanation :-
    3x - y = 7 ⇒ - 3x - 7 = y                     — eq 1
    x + 2y = 6                                     —- eq 2
    x + 2 ( - 3x - 7) = 6 ⇒ x - 6x - 14 = 6
    ⇒ - 5x = 14 + 6 ⇒ - 5x = 20
    ⇒ x = -4
    Step 2 :- substitute value of x and find y
    ⇒ - 3x - 7 = y ⇒ y = - 3 (- 4) - 7
    ⇒ y = 12 - 7
    ∴ y = 5
    x = -4 and y = 5 is the solution of the given pair of equations.


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