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Solve the system of equation 3x - 4y + 1 = 0 & 9x - 7y = 15 using elimination.

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grade82 | Student

Posted June 7, 2013 at 3:56 AM via web

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Solve the system of equation 3x - 4y + 1 = 0 & 9x - 7y = 15 using elimination.

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justaguide | College Teacher | (Level 2) Distinguished Educator

Posted June 7, 2013 at 4:03 AM (Answer #1)

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The following system of linear equations has to be solved:

3x - 4y + 1 = 0 ...(1)

9x - 7y = 15 ...(2)

(2) - 3*(1)

=> 9x - 9x - 7y + 12y - 3 = 15

=> 5y = 18

=> y = 18/5

7*(1) - 4*(2)

=> 21x - 28y + 7 - 36x + 28y = -60

=> 15x = 67

x = 67/15

The solution of the given system of equations is x = 67/15 and y = 18/5

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