Solving Linear Systems

In your previous classes at primary and high school levels, you came across linear equations i.e. equations whose functions if plotted on a plane or graph paper you will end up getting straight lines. Linear equations may have one or more unknowns. For instance; x=3;y=-5;x+y=5;x+y+2z=6;2a+3b+3c-6d=7 and so on. Solving linear equations with 1 unknown and 4 or more unknowns will not be discussed here. Our interest is to solve linear equations with 2 and 3 unknowns. Some quantities in real life may be expressed in linear form, but in reality it is rare to have linear relationships because of the many parameters that are in play. Linear equations are used in real life to explain situations while holding some variables constant. For instance price p of a commodity say a phone may partly depend on demand q of the phones and partly constant. Note, the price cannot go down to zero even if the demand is zero. This may be written as p=bq+k.