Answer:
Hence, 4x
2
−3y
2
−xy should be subtracted.
Step-by-step explanation:
Let q should be subtracted.
Then according to question,
3x
2
−4y
2
+5xy+20−q=−x
2
−y
2
+6xy+20
⇒q=3x
2
−4y
2
+5xy+20−(−x
2
−y
2
+6xy+20)
⇒q=3x
2
−4y
2
+5xy+20+x
2
+y
2
−6xy−20
⇒q=3x
2
+x
2
−4y
2
+y
2
+5xy−6xy+20−20
⇒q=4x
2
−3y
2
−xy+0
Hence, 4x
2
−3y
2
−xy should be subtracted.
