Question

$25a {}^{2} - 4b {}^{2} + 28bc - 49c {}^{2}$

Answer 1

$25a^2 -4b^2 + 28bc -49c^2$

$(5a)^2 -(2b)^2 + 7c(4b - 7c)$
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By Formula $a^2 -b^2 = (a+b)(a-b)$
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(5a+2b)(5a-2b) + 7c[4b-7c]


i hope this will help you


-by ABHAY