विलोपन विधि से दो चर वाले रैखिक समीकरण

Video narration

When you see two unknowns, x and y, where do you begin? Think of a balance scale: keep it level by making the same change on both sides of an equation. One equation with two unknowns can fit many pairs; two equations let you look for a pair that fits both. Take x plus y equals seven, and x minus y equals one. In the elimination method, make one variable cancel. The y terms have opposite signs, so add the equations. The y disappears; two x equals eight. Divide by two: x equals four. Put four into the first equation: four plus y equals seven, so y equals three. Check the pair in both equations: four plus three is seven, and four minus three is one. Both equations balance. So where do you begin? Keep the balance: cancel one variable, solve the other, then substitute back to find its partner.