Welcome :: Homework Help and Answers :: Mathskey.com
Welcome to Mathskey.com Question & Answers Community. Ask any math/science homework question and receive answers from other members of the community.

13,435 questions

17,804 answers

1,438 comments

774,847 users

Algebra HELP?

0 votes
I tried to do these but I keep getting confused, please help.

1) Find the LCM of 9-4x^2, 3-2x, and 3 + 2x

2)18/ 5x^3 multiplied by 5x^2/6

3)x + 2/( x+3)(x-5)(x-1)

4) c-3 divided by 3-c
asked Jul 22, 2014 in ALGEBRA 1 by anonymous

1 Answer

0 votes

1).

First factor each component :

9 - 4x2 = 32 - (2x)2 = (3 + 2x)(3 - 2x)

this means that, (9 - 4x2) is divisible by both (3 + 2x) and (3 - 2x)

(3 - 2x) is prime, and

(3 + 2x) is prime.

The Least Common Multiples of 9 - 4x2 , 3 - 2x, and, 3 + 2x is product of (3 - 2x) and (3 + 2x).

Therefore, the LCM of 9 - 4x2 , 3 - 2x, and, 3 + 2x is 9 - 4x2 .

2).

(18/5x3) * (5x2/6)

= ( 18 * 5x2)/(5x3 * 6)

= ( 6 * 3 * 5x2)/(5x2 * x * 6)

cancel common terms.

= 3/x.

Therefore, (18/5x3) * (5x2/6) = 3/x.

3).

x + {2/[(x + 3)(x - 5)(x - 1)]}

LCM of [(x + 3)(x - 5)(x - 1)] and 1 is [(x + 3)(x - 5)(x - 1)].

= {x[(x + 3)(x - 5)(x - 1)] + 2}/[(x + 3)(x - 5)(x - 1)]

= {x[x3 - 3x2 - 13x + 15] + 2}/[(x + 3)(x - 5)(x - 1)]

= {x4 - 3x3 - 13x2 + 15x + 2}/[(x + 3)(x - 5)(x - 1)].

4).

(c - 3)/(3 - c)

Common out negative 1 from the denominator.

= - (c - 3)/(c - 3)

Cancel common terms.

= - 1.

Therefore, (c - 3)/(3 - c) = - 1.

answered Jul 22, 2014 by lilly Expert

Related questions

asked Jul 10, 2014 in ALGEBRA 1 by anonymous
asked Sep 5, 2014 in ALGEBRA 2 by anonymous
asked Jan 17, 2019 in ALGEBRA 1 by anonymous
asked Jun 11, 2014 in ALGEBRA 1 by anonymous
asked Oct 16, 2020 in GEOMETRY by anonymous
asked Jun 12, 2019 in TRIGONOMETRY by anonymous
...