Tamil Nadu Board Solutions for Chapter: Algebra, Exercise 5: Exercise

Using the identity $(a+b)(a-b)=a^2-b^2$, find the product $(4-mn)(mn+4)$.

Using the identity $(a+b)(a-b)=a^2-b^2$, find the following product $(6x+7y)(6x-7y)$.

Factorise $64x^2-112xy+49y^2$, using suitable identity.

Factorise $a^2+6ab+9b^2-c^2$, using suitable identity.

Simplify $(\mathrm{x}+3)(\mathrm{x}+5)$ followting using the identity $(\mathrm{x}+\mathrm{a})(\mathrm{x}+\mathrm{b})={\mathrm{x}}^2+\mathrm{x}(\mathrm{a}+\mathrm{b})+\mathrm{ab}$ :

Simplify $(\mathrm{y}+6)(\mathrm{y}+8)$ using the identity $(\mathrm{x}+\mathrm{a})(\mathrm{x}+\mathrm{b})={\mathrm{x}}^2+\mathrm{x}(\mathrm{a}+\mathrm{b})+\mathrm{ab}$ :

Simplify $43\times 36$ using the identity $(\mathrm{x}+\mathrm{a})(\mathrm{x}+\mathrm{b})={\mathrm{x}}^2+\mathrm{x}(\mathrm{a}+\mathrm{b})+\mathrm{ab}$ :

Solve: $2x+4<18$, where $x$ is a natural number.