Question

(2a-5b)2
$(2a - 5b) ^{2}$
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Answer 1

$(2a - 5b) ^{2} \\ = (2a) {}^{2} + {(5b)}^{2} - 2(2a)(5b) \\ = 4 {a}^{2} + 25 {b}^{2} - 20ab \\ \\ formulas \: used \: \\ (a - b) {}^{2} = {a}^{2} + b {}^{2} - 2ab$

Answer 2

Answer:

4a square + 25b square - 20ab

Step-by-step explanation:

(2a - 5b)2 = (2a)2 + (5b)2 - 2×2a×5b. {using - (a-b)2 = a2 + b2 - 2ab}

(2a - 5b)2 = (2a)2 + (5b)2 - 2×2a×5b. {using - (a-b)2 = a2 + b2 - 2ab} = 4a2 + 25b2 - 20ab