Question

(x +1)^2-5x(x+3)(x-3)

Answer 1

`\huge \boxed{\mathfrak{Question} \downarrow}`

• (x + 1)² - 5x (x + 3)(x - 3)

`\large \boxed{\mathfrak{Answer \: with \: Explanation} \downarrow}`

`( x + 1 ) ^ { 2 } - 5 x ( x + 3 ) ( x - 3 )`

Use binomial theorem
`\left(a+b\right)^(2)=a^(2)+2ab+b^(2)` to expand
`\left(x+1\right)^(2)`.

`x^(2)+2x+1-5x\left(x+3\right)\left(x-3\right)`

Use the distributive property to multiply -5x by x+3.

`x^(2)+2x+1 + (-5x^(2)-15x)(x-3)`

Use the distributive property to multiply
`-5x^(2)-15x` by x-3 and combine like terms.

`x^(2)+2x+1-5x^(3)+45x`

Combine 2x and 45x to get 47x.

`\boxed{\boxed{\bf\:x^(2)+47x+1-5x^(3) }}`

OR

Follow the same steps till
`x^(2)+2x+1-5x^(3)+45x` and then use the algebraic identity ⇨ a + 2ab + b² = (a + b)²

`\boxed{\boxed{\bf\:-5x^(3)\left(x+1\right)^(2)+45x}}`