What polynomial could you add to 3x4-9x3+5x2-x+7 to get a sum of 3+4x4+3x-x3+3x2? A: -x7+21x2+9x-6
B: 7x5+2x4-3x3+x2+6x-10
C: x4+8x3-2x2+4x-4
Some of you might can tell the exponents

In need of in the diagram, ∠abc is a right angle. ∠dbc = 30°27'40". find the measure of ∠abd.

The price of a visit to the dentist is \$50$50. if the dentist fills any cavities, an additional charge of \$100$100 per cavity gets added to the bill. if the dentist finds nn cavities, what will the cost of the visit be?

Mrs. robinson bought a novel at a bookstore on sale for 20% off its regular price of $29.99. mr chang bought the same novel at a different bookstore for 10% off its regular price of $25. which person received the better discount?