Question

Hello people ~
factorise: x² + 4x - 77​

Answer 1

x = 7

x = -11

Explanation:

x² + 4x = 77​

Complete the square to make it a square of a binomial

x² + 4x + 4 = 77 + 4

(x+2)² = 81

Square root both sides (two solutions)

x + 2 = 9

x = 7

x + 2 = -9

x = -11

Hope this helps :)

Have a nice day!

Answer 2

`\qquad\qquad\huge\underline{\boxed{\sf Answer}}`

Let's solve ~ ☂

`\qquad \sf  \dashrightarrow \: {x}^(2) + 4x - 77`

`\qquad \sf  \dashrightarrow \: {x}^(2) + 11x - 7x - 77`

`\qquad \sf  \dashrightarrow \: {x}^{} (x + 11) -7(x + 11)`

`\qquad \sf  \dashrightarrow \: {}^{} (x + 11)(x - 7)`