Question

$if a = 4x { }^{2} + y {}^{2} - 6xy \: b = 3y {}^{2} + 12x {}^{2} + 8y8xy \: c = 6x {}^{2} + 8y {}^{2} + 6xy \: find \: a + b + c \: (a - b) \: 2 a+b \: a - 3b$
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Answer 1

Step-by-step explanation:

A=4x2+y2−6xy

B=3y2+12x2+8xy

C=6x2+8y2+6xy

(A−B)−C=[(4x2+y2−6xy)−(3y2+12x2+8xy)]−(6x2+8y2+6xy)

=(−8x2−2y2−14xy)−(6x2+8y2+6xy)

=−14x2−10y2−20xy