Which of the following Pair of linear equations are consistent or inconsistent xy 8, 3x -- 3y = 16

Solution:

For any pair of linear equation,

a₁ x + b₁ y + c₁ = 0

a₂ x + b₂ y + c₂ = 0

a) a₁/a₂ ≠ b₁/b₂ (Intersecting Lines/uniqueSolution)

b) a₁/a₂ = b₁/b₂ = c₁/c₂ (Coincident Lines/Infinitely many Solutions)

c) a₁/a₂ = b₁/b₂ ≠ c₁/c₂ (Parallel Lines/No solution)

(i) x + y = 5, 2x + 2y = 10

a₁/a₂= 1/2

b₁/b₂= 1/2

c₁/c₂= -5/(-10) = 1/2

From the above,

a₁/a₂ = b₁/b₂ = c₁/c₂

Therefore, lines are coincident and have infinitely many solutions. Hence, they are consistent.

x + y - 5 = 0

y = - x + 5

y = 5 - x

2x + 2y - 10 = 0

2y = 10 - 2x

y = 5 - x

Which of the following Pair of linear equations are consistent or inconsistent xy 8, 3x -- 3y = 16

All the points on coincident line are solutions for the given pair of equations.

(ii) x - y = 8, 3x - 3y =16

a₁/a₂ = 1/3

b₁/b₂ = -1/(-3) = 1/3

c₁/c₂ = - 8/(-16) = 1/2

From the above,

a₁/a₂ = b₁/b₂ ≠ c₁/c₂

Therefore, lines are parallel and have no solution.

Hence, the pair of equations are inconsistent.

(iii) 2x + y - 6 = 0, 4x - 2y - 4 = 0

a₁/a₂ = 2/4 = 1/2

b₁/b₂ = 1/(-2) = -1/2

c₁/c₂ = -6/(-4) = 3/2

From the above,

a₁/a₂ ≠ b₁/b₂

Therefore, lines are intersecting and have a unique solution.

Hence, they are consistent.

2x + y - 6 = 0

y = 6 - 2x

4x - 2y - 4 = 0

2y = 4x - 4

y = 2x - 2

Which of the following Pair of linear equations are consistent or inconsistent xy 8, 3x -- 3y = 16

x = 2 and y = 2 are solutions for the given pair of equations.

(iv) 2x - 2y - 2 = 0, 4x - 4y - 5 = 0

a₁/a₂ = 2/4 = 1/2

b₁/b₂ = -2/(-4) = 1/2

c₁/c₂ = -2/(-5) = 2/5

From the above,

a₁/a₂ = b₁/b₂ ≠ c₁/c₂

Therefore, lines are parallel and have no solution.

Hence, the pair of equations are inconsistent.

☛ Check: NCERT Solutions for Class 10 Maths Chapter 3

Video Solution:

Which of the following pairs of linear equations are consistent/inconsistent? If consistent, obtain the solution graphically: (i) x + y = 5, 2x + 2y = 10 (ii) x - y = 8, 3x - 3y =16 (iii) 2x + y - 6 = 0, 4x - 2y - 4 = 0 (iv) 2x - 2y - 2 = 0, 4x - 4y - 5 = 0

NCERT Solutions for Class 10 Maths - Chapter 3 Exercise 3.2 Question 4

Summary:

On comparing the ratios of the coefficients of the following pairs of linear equations, we see that (i) x + y = 5, 2x + 2y = 10 have infinitely many solutions. Hence, they are consistent. (ii) x - y = 8, 3x - 3y =16 are parallel and have no solution.Hence, the pair of equations are inconsistent. (iii) 2x + y - 6 = 0, 4x - 2y - 4 = 0 are intersecting and have a unique solution. Hence, they are consistent. (iv) 2x - 2y - 2 = 0, 4x - 4y - 5 = 0 are parallel and have no solution. Hence, the pair of equations are inconsistent.

☛ Related Questions:

Which of the following pairs of linear equations are consistent/ inconsistent? If consistent, obtain the solution graphically:

x – y = 8, 3x – 3y = 16

x - y = 8

3x - 3y = 16

`a_1/a_2 = 1/3, b_1/b_2 = (-1)/-3 = 1/3 and c_1/c_2 = 8/16 = 1/2`

Since `a_1/a_2 = b_1/b_2 ≠ c_1/c_2`

Therefore, these linear equations are parallel to each other and thus have no possible solution. Hence, the pair of linear equations is inconsistent.

Concept: Graphical Method of Solution of a Pair of Linear Equations

  Is there an error in this question or solution?

The coach of a cricket team buys 3 bats and 6 balls for Rs. 3900. Later, she buys another bat and 3 more balls of the same kind for Rs. 1300. Represent this situation algebraically and graphically.

Let the cost of 1 bat be Rs. x and cost of I ball be Rs.y

Case I. Cost of 3 bats = 3x

Cost of 6 balls = 6y

According to question,

3x + 6y = 3900

Case II. Cost of I bat = x

Cost of 3 more balls = 3y

According to question,

x + 3y = 1300

So, algebraically representation be

3x + 6y = 3900

x + 3y = 1300

Graphical representation :

We have,    3x + 6y = 3900

⇒    3(x + 2y) = 3900

⇒    x + 2y = 1300

⇒    a = 1300 - 2y

Thus, we have following table :

Which of the following Pair of linear equations are consistent or inconsistent xy 8, 3x -- 3y = 16

We have,    x + 3y = 1300

⇒    x = 1300 - 3y

Thus, we have following table :

Which of the following Pair of linear equations are consistent or inconsistent xy 8, 3x -- 3y = 16

When we plot the graph of equations, we find that both the lines intersect at the point (1300. 0). Therefore, a = 1300, y = 0 is the solution of the given system of equations.

Which of the following Pair of linear equations are consistent or inconsistent xy 8, 3x -- 3y = 16