Solve the set of simultaneous equation.2x – 7y = 7; 3x + y = 22

1.	Solve the set of simultaneous equation.2x – 7y = 7; 3x + y = 22
Answer» 2x – 7y = 7 …(i) 3x + y = 22 ∴ y = 22 – 3x ……(ii) Substituting y = 22 – 3x in equation (i), 2x – 7(22 – 3x) = 7 ∴ 2x – 154 + 21x = 7 ∴ 23x = 7 + 154 ∴ 23x = 161 ∴ x = \(\frac{161}{23}\) ∴ x = 7 Substituting x = 7 in equation (ii), y = 22 – 3x ∴ y = 22 – 3(7) ∴ 7 = 22 -21= 1 ∴ (7, 1) is the solution of the given equations

Answer»

2x – 7y = 7 …(i)

3x + y = 22

∴ y = 22 – 3x ……(ii)

Substituting y = 22 – 3x in equation (i),

2x – 7(22 – 3x) = 7

∴ 2x – 154 + 21x = 7

∴ 23x = 7 + 154

∴ 23x = 161

∴ x = \(\frac{161}{23}\)

∴ x = 7

Substituting x = 7 in equation (ii),

y = 22 – 3x

∴ y = 22 – 3(7)

∴ 7 = 22 -21= 1

∴ (7, 1) is the solution of the given equations

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