Question

x(x-1)=20 solve this​

Answer 1

Answer:

$= > x(x - 1) = 20 \\ \\ = > (x \times x) - (x \times 1) = 20 \\ \\ = > {x}^{2} - x = 20 \\ \\ = > {x}^{2} - x - 20 = 0 \\ \\ = > {x}^{2} - 5x + 4x - 20 = 0 \\ \\ = > x(x - 5) + 4(x - 5) = 0 \\ \\ = > (x - 5)(x + 4) = 0 \\ \\ = > x - 5 = 0 \: \: \: or \: \: \: x + 4 = 0 \\ \\ = > x = 5 \: \: \: or \: x = - 4$

Answer 2

Answer :

x = -4 or 5

Step-by-step explanation:

x(x-1) = 20

x(x) - x(1) = 20

x² - x = 20

x² - x - 20 = 0

x² - 5x + 4x -20 = 0

[ a/s = x ; M = 20x² ]

x(x - 5) + 4(x - 5) = 0

(x + 4)(x - 5) = 0

We get -

x + 4 = 0

x = 0-4 or -4

x - 5 = 0

 x = 0+5 or 5