Question

Which of the following lines contain the point (1, 2)?

• A. x + 2y = 5
• B. 2x + y = 5
• C. 4x – y = 5
• D. 3x – 2y = 1

Answer 1

The correct option is A

x + 2y = 5

Every point on the line is a solution of the line. It can also be said that every solution of a linear equation is a point on the line representing it.

Substituting (1,2) in the options,

$x+2y=5\Rightarrow 1+2\left(2\right)=5$
Satisfies the equation.

$2x+y=52\left(1\right)+2\ne 5$
Does not satisfy the equation.

$4x–y=5\Rightarrow 4\left(1\right)–2\ne 5$
Does not satisfy the equation.

$3x–2y=1\Rightarrow 3\left(1\right)–2\left(2\right)\ne 1$
Does not satisfy the equation.