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Question
Complete the activity to find the value of x.
3x + 2y = 11 …(i) and 2x + 3y = 4 …(ii)
Solution:
Multiply equation (i) by _______ and equation (ii) by _______.
`square` × (3x + 2y = 11) ∴ 9x + 6y = 33 …(iii)
`square` × (2x + 3y = 4) ∴ 4x + 6y = 8 …(iv)
Subtract (iv) from (iii),
`square` x = 25
∴ x = `square`
Solution
3x + 2y = 11 …(i) and 2x + 3y = 4 …(ii)
Multiply equation (i) by 3 and equation (ii) by 2.
3 × (3x + 2y = 11) ∴ 9x + 6y = 33 …(iii)
2 × (2x + 3y = 4) ∴ 4x + 6y = 8 …(iv)
Subtract (iv) from (iii),
5 x = 25
∴ x = `25/5`
∴ x = 5
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