Question

10. Factorise : 4x- 20x +25​

Answer 1

Step-by-step explanation:

${4x}^{2} - 20x + 25 \\ = {4x}^{2} - 10x - 10x + 25 \\ = 2x(2x - 5) - 5(2x - 5) \\ = (2x - 5)(2x - 5) = 0 \\ 2x - 5 = 0 \: \: \: \: 2x - 5 = 0 \\ 2x = 5 \: \: \: \: \: 2x = 5 \\ x = \frac{5}{2} \: \: \: \: \: x = \frac{5}{2}$