Question

(2y + 5) (2y - 5) factorise it​

Answer 1

Answer:

4y²-25

Step-by-step explanation:

Using (a+b)(a-b)=a²-b².

4y²-25

Answer 2

Step-by-step explanation:

(2y + 5)(2y - 5)

2y x 2y = 4y^2

2y x -5 = -10y

5 x 2y = 10y

5 x -5 = -25

= 4y^2 -10y + 10y - 25 (10, -10 cancel)

= 4y^2 - 25

- 4y^2 = -25 (- + - = positive)

4y^2 = 25

y^2 = 25 - 4

y^2 = 21

y = root of 25.

Hope It Helps