Answer:
-3x^{4} + 19x^{3} - 38x^{2} + 25x - 3
Step-by-step explanation:
1) distribute x² into (-3x² + 7x - 1) to get: -3x^{4} + 7x³ - x²
2) distribute -4x into (-3x² + 7x - 1) to get: 12x³ - 28x + 4x
3) distribute 3 into (-3x² + 7x - 1) to get: -9x² + 21x - 3
4) combine all the answers together into one equation:
-3x^{4} + 7x³ - x² + 12x³ - 28x² + 4x - 9x² + 21x - 3
5) combine like terms:
7x³ + 12x³ = 19x³
-x² + -28x² + -9x² = -38x²
4x + 21x = 25x
6) combine answers together into one equation:
-3x^{4} + 19x³ - 38x² + 25x - 3
Ryan bought 25 packs because 25 is equal to one-fourth.
I believe that -16 is the answer to the question above.
Hope this helps and please enjoy Brainly! -ZeusROX
For the circumference, you actually multiply by 20 because of the formula πd = C [OR 2πr = C]. You meant to double the radius.
