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Solve the Following Pair of Linear (Simultaneous) Equation Using Method of Elimination by Substitution : 2x - 3y + 6 = 0 2x + 3y - 18 = 0

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Question

Solve the following pair of linear (simultaneous) equation using method of elimination by substitution :
2x - 3y + 6 = 0
2x + 3y - 18 = 0

Sum
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Solution

2x - 3y + 6 = 0
⇒ 2x = 3y - 6
⇒ x = `[ 3y - 6 ]/2`                     ...(1)
And,
2x + 3y - 18 = 0
⇒ 2`([3y - 6]/2)`+ 3y = 18          ...[From(1)]

⇒ 3y - 6 + 3y = 18
⇒ 6y = 24
⇒ y = 4
Substituting the value of y in (1), we have
x = `[ 3 xx 4 - 6]/2 = [12 - 6]/2 = 6/2 = 3`
∴ Solution is x = 3 and y = 4.

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Methods of Solving Simultaneous Linear Equations by Elimination Method
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Chapter 6: Simultaneous (Linear) Equations [Including Problems] - Exercise 6 (A) [Page 79]

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Selina Concise Mathematics [English] Class 9 ICSE
Chapter 6 Simultaneous (Linear) Equations [Including Problems]
Exercise 6 (A) | Q 12 | Page 79

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