Question

(i) (2x + 5)2 - (2x - 5)​

Answer 1

${(2x + 5)}^{2} - (2x - 5) \\ = 4 {x}^{2} + 20x + 25 - 2x + 5 \\ = 4 {x}^{2} + 18x + 30$

Answer 2

Answer:

multiply 2x*2 and 5*2

(4x +10)-(2x-5)

4x+10-2x+5

4x-2x+10+5

2x+15