Question

3. 2x^2+6x-7x+8-3x^2+1
A. 2x^2+x+9
B. -2x^2-x-9
C. -x^2-x+9
D. x^2+9

4. What are the coefficents in the polynomial 4x^2+3x-3
A. 4,-3,-3
B. 4,3
C. 4,3,3
D. -4,-3

6. (7x^2-x-2)-(6x^3+3)
A. 6x^3-+7x^2-x-5
B. -6x^3+7x^2-x+1
C. -x^3-x-5
D. x^2-x+1

7. Suppose you earn 6t-2 dollars on Monday and 9t-6 dollars on tuesday. What were your total earnings? Simplify your answer.
A. 15t-4
B. 15t+8
C. -3t-4
D. -3t+8

15. (1.4*10^1)(8*10^4)
A. 9.4*10^4
B. 9.4*10^5
C. 1.12*10^5
D. 1.12*10^6

18. -x(7x-8)
A. 6x^2-9x
B. -7x-8x
C. -7x^2+8x
D. 7x+8x

19. 4k^2(-3k^2-4k+5)
A. -12k^4-16k^3+20k^2
B. 12k^4-16k^3=9k^2
C. -12k^3+20k
D. k^4+9k^2

20. (2k+1)(k-3)
A. 2k^2-7k+4
B. 2k^2-3k+4
C. 2k^2+9k+4
D. 2k^2-7k-4

21. (3k+2k)(y+3)
A. -3y^2-7y+6
B. 3y^2-11y+6
C. 3y^2-7y-6
D. 3y^2+11y+6

Answer 1

#7 has a typo. Either A or B would work, depending on what it was.

No ideas on any of the others?

Answer 2

I have a hard time with these...

Answer 3

I think that 3 is B... 4 I think is B... 6 is maybe A... 7 I think is B... 15 is maybe C... 18 is possibly C... 19 is maybe B... 20 is I think C... and 21 is possibly A? Any way.. I don't think that these are correct...

Answer 4

2x^2+6x-7x+8-3x^2+1
2x^2-3x^2 + 6x-7x + 8+1
-x^2-x+9

4x^2+3x-3
4,3,-3
Typo somewhere

(7x^2-x-2)-(6x^3+3)
7x^2-x-2-6x^3-3
-6x^3+7x^2-x-5

6t-2 + 9t-6
15t-8

(1.4*10^1)(8*10^4)
(1.4*8)* (10^1*10^4)
11.2 * 10^5
1.12 * 10^6

#18C ok

4k^2(-3k^2-4k+5)
4k^2(-3k^2) + 4k^2(-4k) + 4k^2(5)
-12k^4 - 16k^3 + 20k^2

(2k+1)(k-3)
2k(k) + 2k(-3) + 1(k) + 1(-3)
2k^2 -6k + k - 3
2k^2-5k-3

#21D

Judging from the number of typos present, it's hard to say. Clearly you are just guessing.