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Question
Solve the following simultaneous equation.
x + y = 11 ; 2x - 3y = 7
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Solution
x + y = 11 ...(I)
2x - 3y = 7 ...(II)
Multiply (I) with 3
3x + 3y = 33 ...(III)
Adding (II) and (III)
2x - 3y = 7
3x + 3y = 33
+
5x = 40
x = `40/5`
⇒ x = 8
Putting the value of x in (I)
8 + y = 11
y = 11 - 8
⇒ y = 3
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