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# Algebra

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Hi there, having trouble with these three here. Thanks for any help.

1.     Factor the expression using the four train cars strategy from class: x^3+6x^2-25x-150

1. Solve the equation p2 + 16p = 17 by completing the square method. Show your work.    SHOW how you complete the square, show steps.

p2 + 16p + ____ = 17 + ____

1. Multiply the polynomials (a2 + 4a – 1) and (7a - 2). Simplify the answer. Show your work.

Mar 23, 2021

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1. Don't  really  know   what  the four train car  stategy is....but....

x^3 +6x^2 - 25 x - 150   =

(x^2) ( x + 6)  - (25)(x + 6)   =

(x^2 - 25) ( x + 6)  =

(x + 5) ( x - 5) ( x + 6)

2.  p^2 + 16p  = 17

Take 1/2 of 16  =  8

Square it  =  64

p^2  + 16p + 64  = 17 + 64

Factor the left side....simplify the right

(p + 8)^2  = 81

Take both roots

p + 8 =  sqrt (81)                    p + 8 = -sqrt (81)

p + 8  =  9                               p + 8 =  -9

p = 9 - 8                                 p =  -9 -8

p = 1                                        p = -17

3)

(a^2 + 4a – 1)  (7a - 2)   =

a^2 * 7a  - 2a^2  + 4a*7a + 4a(-2)  - 1(7a)  -1(-2)  =

7a^3  - 2a^2 + 28a^2 - 8a - 7a  + 2  =

7a^3  + 26a^2  - 15a  +  2   Mar 23, 2021