Simplify $$(2z-5y)^2+(5z+2y)^2-25z^2$$​.

Correct option is B

Given 

​$$(2z - 5y)^2 + (5z + 2y)^2 - 25z^2$$

Formula Used-

​$$(a+b)^2 = a^2+b^2+2ab$$

$$(a-b)^2=a^2+b^2-2ab$$

Solution-

​​$$(2z - 5y)^2 = (2z)^2 - 2(2z)(5y) + (5y)^2 = 4z^2 - 20zy + 25y^2$$

$$(5z + 2y)^2 = (5z)^2 + 2(5z)(2y) + (2y)^2 = 25z^2 + 20zy + 4y^2$$

Substitute these expanded forms into the original expression

$$(2z - 5y)^2 + (5z + 2y)^2 - 25z^2 = (4z^2 - 20zy + 25y^2) + (25z^2 + 20zy + 4y^2) - 25z^2$$

$$= 4z^2 + 25z^2 - 25z^2 + (-20zy + 20zy) + 25y^2 + 4y^2$$

$$= 4z^2 + 25z^2 - 25z^2 + 0 + 25y^2 + 4y^2$$

$$= 4z^2 + 29y^2$$​​​​​​​

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