Question

Can someone please check my factoring homework? I'm not sure if I did everything correctly. I'll give a medal :)

1. Factor: X^2+9X+20
Answer: (X+5)(X+4)

2. Factor: X^2-14X+40
Answer: (X-4)(X-10)

3. Factor: X^2+6X+3
Answer: (X+2)(X+3)

4.Factor: X^2-5X-50
Answer: (X+5)*X-10)

5. Factor: 3M^2+MT-10T^2
Answer: (M+2T)(3M-5T)

6. Factor: 25-y^2
Answer: -(y+5)(y-5)

7. Factor: h^3+9h
Answer: h(h^2+9)

8. Factor: a^3+64
(a+4)(a^2-4a+16)

9.Factor: 9y^3-4y
Answer: y(3y+2)(3y-2)

10. Factor: S^2+9
Answer: (S+3)(S-3)

Answer 1

only #3 and #10 are wrong

Answer 2

For number 10 would the answer be Prime?

Answer 3

yes
same for #3

Answer 4

Okay thanks so much, can you check 10 more? I have one more factoring work sheet

Answer 5

ok
you know you can check these yourself by just multiplying it out and comparing to original expression

Answer 6

11. Factor: m^3-8m^2+m-8
Answer: (m^2+1)(m-8)

12. Factor y^3+y-6y^2-6
Answer: (y-6)(y^2+1)

13. Solve: 5x^2+6x+8=0
Answer: No solution

14. Solve: 3x^2-19x+28=0
Answer: ?

15. Solve: (4x-1)(x+9)=0
Answer: x=3, x=-5

16. Solve: (x+3)(x-3)=0
Answer: x=-3, x=3

17. Solve: (4x-1)(x+9)=0
Answer: X=1/4 X==9

18. Solve: 2x^2+5x=3
Answer: x=0 x=-1

Answer 7

15. Solve: (4x-1)(x+9)=0
Answer: x=3, x=-5

wrongggggggggggg.
solve
x-9=0

and then solve for 4x-1=0

Answer 8

looks good except for 14,15,18

Answer 9

@dumbcow Can you show me how to do them?

Answer 10

Also for number 15 I meant to put the question as : X^2-2x-15=0
Answer: x=3, x=-5

Answer 11

oooooh that makes better sense. but the signs for the answers are switched

(x+3)(x-5) = 0

Answer 12

#14

(3x - __ )(x - __)

you need 2 numbers that multiply to 28 ---> (2,14) or (4,7)
try a pair and check to see if "x" term is -19

(3x - 2) (x-14) ----> -2x -14(3x) = -44x
try again

(3x - 7)(x-4) ----> -7x -4(3x) = -19x

Answer 13

@UsukiDoll Thanks, yeah I had accidentally types a different question. @dumbcow Oh okay thank you! :)

Answer 14

18)

2x^2 +5x -3 = 0

(2x + ___) (x - __)

2 numbers must multiply to -3 --> (1,-3) or (-1,3)

(2x +1)(x -3)
check x term ---> x -3(2x) = -5x
we need positive 5 , switch the signs

(2x -1)(x +3)

Answer 15

Thanks again! :)

Answer 16

yw