Question

evaluate (4x -5y) 2

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Answer 1

Answer:

8x-10y that's all...........

Answer 2

Answer:

16x²+25y²-40xy

Step-by-step explanation:

(4x-5y)². (a-b)²=a²+b²-2ab

(4x)²+(5y)²-2(4x)(5y)

16x²+25y²-40xy

This question is solved by algebric identity

Algebraic Identities

(x + y)2 = x2 + 2xy + y2

(x – y)2 = x2 – 2xy + y2

x2 – y2 = (x + y) (x – y)

(x + a) (x + b) = x2 + (a + b)x + ab.

(x + y + z)2 = x2 + y2 + z2 + 2xy + 2yz + 2zx.

(x + y)3 = x3 + y3 + 3xy(x + y)

(x – y)3 = x3 – y3 – 3xy(x – y)

x3 + y3 + z3 – 3xyz = (x + y + z) (x2 + y2 + z2 – xy – yz – zx)

We have to find what is given in the question from above it will be easier to do so practice some questions.

Hope it helps you.Thank you for your time