Wednesday, June 16, 2010

Linear Equations Problems

Linear equations problems are simple problems of algebra and also basic problems solved in lower grades as well as in higher grades. Before solving problems on linear equations, let's know the definition of linear equation.

Equation


An equation is an equality connecting some unknowns. The unknowns are represented by "letters" and are called "the variables". If the equation has only one unknown, it is called "an equation in one variable". The word "Linear" means "of degree one".

An equation involving one variable with highest power 1, is called a linear equation in the variable.

Linear equation problems


(i) 5x + 7 = 22
Solution :
5x = 22 - 7
x = 15/5
x = 3

(ii) 2y – 5 = 4y – 9
Solution :
-5 + 9 = 4y - 2y
+ 4 = 2y
4/2 = y
so y = 2

(iii) z/3 – z/4 = 8
Solution :
(4z - 3z)/12 = 8
z/12 = 8
z = 96