← CBSE Class 10 (age 15) Mathematics ยท Pair of Linear Equations in Two Variables

Graphical Method and Consistency

Practice Quiz

Q1. What does the intersection of two lines indicate?

โœ” The point where lines meet satisfies both equations, giving a unique solution.

Q2. Which condition represents parallel lines?

โœ” Parallel lines have equal slope ratios but different intercepts.

Q3. Infinite solutions occur when lines are:

โœ” Coincident lines overlap completely, satisfying the equations at every point.
Show transcript
[Slide 1] Visualizing Linear Equations
Imagine drawing two straight lines on a graph paper. Where they cross is your answer. If they never meet, there is no solution.

[Slide 2] Consistency Cases Explained
We check the ratios of coefficients to predict the graph. Unequal ratios mean one intersection point. Equal ratios might mean parallel or same lines.

[Slide 3] Solving x + y = 3
Let us solve the system x plus y equals three and two x minus y equals zero. First, find coordinates for the first equation.

[Slide 4] Solving 2x - y = 0
For the second line, use points zero comma zero and one comma two. Now draw both lines carefully on your axes.

[Slide 5] Common Graphing Mistakes
Students often draw lines too roughly or scale axes wrong. Always verify your intersection point satisfies both equations.

[Slide 6] Key Takeaways Summary
Remember, intersecting lines mean consistent unique solutions. Parallel lines are inconsistent, while overlapping lines have infinite solutions.