Practice30Create account

(5, 2) is a solution of , since 15 − 8 = 7. Is (2, 5) also a solution?

Class 9Linear Equations in Two VariablesLinear Equations
  • AYes — the same two numbers appear, so the equation still holds
  • BNo — substituting gives 3(2) − 4(5) = −14, not 7
  • CYes — swapping and never changes the value
  • DNo — a linear equation in two variables can have only one solution

Step-by-Step Solution

Order matters in an ordered pair: in (2, 5), and , giving 6 − 20 = −14 ≠ 7. The equation does have infinitely many other solutions — just not this one.
Answer: B) No — substituting gives 3(2) − 4(5) = −14, not 7

Key idea: What does a 'solution' look like?

For an equation in TWO variables, a solution is a PAIR , not a single number.

Example: . Try (1, 5): ✓. So (1, 5) is a solution.

Try (0, 7), (2, 3), (3, 1), (−1, 9) — all work. There are infinitely many. Two variables, one equation → one degree of freedom remaining.

Master this chapter in 30 minutes a day.

Don't just memorise the answer — build a daily practice habit.

Practice 5 Similar Questions Free →

All Linear Equations in Two Variables practice questions

More Class 9 Linear Equations in Two Variables practice

Which point does NOT lie on the line x = −6?Sonia is 3 years older than her brother. Taking Sonia’s age as x years and her brother’s…In the equation 4x − 3y = 24, find y when x = 3.Written as ax + by + c = 0, the equation y = −7x gives which values?Which statement about the graph of 5x + 2y = 20 is TRUE?