Question

21. What should be subtracted from 3x2 - 4y2 + 5xy + 20 to obtain x2 - y2 + 6xy + 20%
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Answer 1

Answer:

3x²-4y²+5xy+20

x² -y² +6xy+20

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+2x²-3y²+xy+0

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Answer 2

Answer:

$3 {x}^{2} - 4 {y}^{2} + 5xy + 20 - (x ^{2} - {y}^{2} + 6xy + 20) \\ = 3 {x}^{2} −4y2+5xy+20− {x}^{2} + {y}^{2} - 6xy - 20 \\ =2 {x}^{2} - 3 {y}^{2} - xy$