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Question
For the equation 3x − 2𝑦 = 17, find the value of x when y = −1 and find the value of y when x = 3
Solution
Substituting y = – 1 in 3x – 2y = 17, we get
3x – 2(–1) = 17
∴ 3x + 2 = 17
∴ 3x = 17 – 2
∴ 3x = 15
∴ x = `15/3` = 5
Substituting x = 3 in 3x – 2y = 17, we get
3(3) – 2y = 17
∴ 9 – 2y = 17
∴ 2y = 9 – 17
∴ 2y = – 8
∴ y = `(-8)/2` = – 4
∴ The value of x is 5 when y = −1 and the value of y is – 4 when x = 3.
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