#### notes

1) While solving an equation, Sarita does the following.

3x + x + 5x = 72

Therefore 8x = 72

and so, x = `72/8 = 9`

Coefficient 1 of a term is usually not shown. But while adding like terms, we include it in the sum.

2) Appu did the following:

For x = –3 , 5x = 5 – 3 = 2

Is his procedure correct? If not, correct it.

Remember to make use of brackets, while substituting a negative value.

**Note : **

1) when you square a monomial, the numerical coefficient and each factor has to be squared.

2) While dividing a polynomial by a monomial, we divide each term of the polynomial in the numerator by the monomial in the denominator.

3) Make sure, before applying any formula, whether the formula is really applicable.

4) when you multiply the expression enclosed in a bracket by a constant (or a variable) outside, each term of the expression has to be multiplied by the constant (or the variable).