8th Class Mathematics Algebraic Expressions Addition and Subtraction of Algebraic Expressions

         Addition and Subtraction of Algebraic Expressions

While adding or subtracting the algebraic expressions we add or subtract the like terms of the expression. While adding or subtracting the like terms of the algebraic expression we add or subtract the coefficients of the algebraic expression. But in case of multiplication or division we normally multiply or divide each term of one expression with the each term of the other expression.  

Add: \[3x+\text{5y}+\text{8z}\] and \[8x+100\text{y-18z}\]

Solution:                

\[=3x+5y+8z+8x+100y-18z\]                

\[=(3+8)x+(5+100)y+(8-18)z\]                

\[=11x+105y-10z\]  

            Like Terms and Unlike Terms

The terms having same order of variables are called like terms and the terms which a do not have same order of variables are called unlike terms.

\[7x,-14x,25x\] are like terms while \[8x,9xy,78zx\] are unlike terms.