Question 3
- On comparing the ratios , and , find out whether the following pair of linear equations are consistent, or inconsistent.
(i) ;
(ii) ;
(iii) ;
(iv) ;
(v) ;
We compare the ratios of coefficients to determine consistency.
Step 1 — Analyze Part (i)
Let's write the equations in standard form. The first equation is . The second equation is . We identify the coefficients. , , . , , .
Now, we calculate the ratios.
We compare these two ratios. This means . The lines intersect at one point.
Step 2 — Analyze Part (ii)
Let's write the equations in standard form. The first equation is . The second equation is . We identify the coefficients. , , . , , .
Now, we calculate the ratios.
The first two ratios are equal. So, we calculate the third ratio. Now, we compare all three ratios. This means . The lines are parallel and do not intersect.
Step 3 — Analyze Part (iii)
Let's write the equations in standard form. The first equation is . The second equation is . We identify the coefficients. , , . , , .
Now, we calculate the ratios.
We compare these two ratios. This means . The lines intersect at one point.
Step 4 — Analyze Part (iv)
Let's write the equations in standard form. The first equation is . The second equation is . We identify the coefficients. , , . , , .
Now, we calculate the ratios.
The first two ratios are equal. So, we calculate the third ratio. Now, we compare all three ratios. This means . The lines are coincident and have many solutions.
Step 5 — Analyze Part (v)
Let's write the equations in standard form. The first equation is . The second equation is . We identify the coefficients. , , . , , .
Now, we calculate the ratios.
The first two ratios are equal. So, we calculate the third ratio. Now, we compare all three ratios. This means . The lines are coincident and have many solutions.
Answer
(i) Consistent (ii) Inconsistent (iii) Consistent (iv) Consistent (v) Consistent
More questions in Exercise 3.1
Form the pair of linear equations in the following problems, and find their solutions graphically.
(i) 10 students of Class X took part in a Mathematics quiz. If the number of girls is 4 more than the number of boys, find the number of boys and girls who took part in the quiz.
(ii) 5 pencils and 7 pens together cost ₹ 50, whereas 7 pencils and 5 pens together cost ₹ 46. Find the cost of one pencil and that of one pen.
- On comparing the ratios , and , find out whether the lines representing the following pairs of linear equations intersect at a point, are parallel or coincident:
(i)
(ii)
(iii)
- On comparing the ratios , and , find out whether the following pair of linear equations are consistent, or inconsistent.
(i) ;
(ii) ;
(iii) ;
(iv) ;
(v) ;
- Which of the following pairs of linear equations are consistent/inconsistent? If consistent, obtain the solution graphically:
(i) ,
(ii) ,
(iii) ,
(iv) ,
- Half the perimeter of a rectangular garden, whose length is more than its width, is . Find the dimensions of the garden.
- Given the linear equation , write another linear equation in two variables such that the geometrical representation of the pair so formed is:
(i) intersecting lines
(ii) parallel lines
(iii) coincident lines
- Draw the graphs of the equations and . Determine the coordinates of the vertices of the triangle formed by these lines and the -axis, and shade the triangular region.