By equating coefficients of variables, solve the following equation. x - 2y = -10 ; 3x - 5y = -12 - Algebra

Question

By equating coefficients of variables, solve the following equation.

x − 2y = −10 ; 3x − 5y = −12

Sum

Solution

x − 2y = −10 ...(I)

3x − 5y = −12 ...(II)

Multiply (I) with 3

3x − 6y = −30 ...(III)

Subtracting (II) from (III) we get,

3x − 6y = −30
3x − 5y = −12
- + +

−y = −18

⇒ y = 18

Putting the value of y in (I) we get,

∴ x − 2y = −10

⇒ x − 2 × 18 = −10

⇒ x = −10 + 36 = 26

Thus, x = 26, y = 18

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Algebraic Methods of Solving a Pair of Linear Equations - Elimination Method

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Q (3) (iii)Q (3) (ii)Q (3) (iv)

Chapter 5: Linear Equations in Two Variables - Problem Set 5 [Page 91]

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Balbharati Mathematics 1 [English] Standard 9 Maharashtra State Board

Chapter 5 Linear Equations in Two Variables
Problem Set 5 | Q (3) (iii) | Page 91

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