15^2-21x-18 cannot factor, say it has a bug.

I get this a lot. What is the problem

The exact equation is

15x^2 - 21x - 18

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

=3{5x^2 -(10-3)x -6 }

=3{5x^2 - 10x + 3x -6}

=3{5x(x - 2) + 3(x-2)}

=3(x-2)(5x+3) these are the factors

Thanks

Zulfikar Ali

ali_zulfikar@yahoo.com

9899780221

Posted on Feb 06, 2009

Do a prime factorization of the two numbers. Use condensed (power) notation for each prime factor.

Example

N1=(2^5)*(3^4)*(7^2)(11^3)

N2=(2^4)*(5^6)*(11)

2 is a factor in N1 and N2, the smallest power of 2 is 4, thus 2^4 is common to N1, and N1. You could write 2^5=2*2^4

11 is a factor in N1, and N2, the smallest exponent of 11 is 1, thus 11 is a common factor of N1 and N2.

Highest common factor of N1 and N2 is (2^4)*11

Example

N1=(2^5)*(3^4)*(7^2)(11^3)

N2=(2^4)*(5^6)*(11)

2 is a factor in N1 and N2, the smallest power of 2 is 4, thus 2^4 is common to N1, and N1. You could write 2^5=2*2^4

11 is a factor in N1, and N2, the smallest exponent of 11 is 1, thus 11 is a common factor of N1 and N2.

Highest common factor of N1 and N2 is (2^4)*11

Sep 02, 2014 | Mathsoft Educational & Reference Software

The prime factors are 2, 3, and 5. If you include the non-prime factors, you also have 1, 6, 10, 15, and 30.

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2, 3, and 7 are the prime factors. If you include the non-primes then the factors are 1, 2, 3, 4, 6, 7, 12, 14, 21, 28, 41, and 84.

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There are three prime factors: 7, 11, and 13.

Mar 29, 2014 | Educational & Reference Software

The prime factors are 2, 3, and 5. If you include the non-prime factors then 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120.

Feb 16, 2014 | Educational & Reference Software

The product of any number and a positive fraction less than one is always less than the number. If both factors are less than one then the product is less than either factor.

Dec 02, 2013 | Mathsoft Educational & Reference Software

The prime factors of 3200 and 800 are 2 and 5.

The prime factors of 2400 and 1200 are 2, 3, and 5.

The prime factors of 2400 and 1200 are 2, 3, and 5.

Sep 17, 2013 | Educational & Reference Software

The current area of the pond is 18m by 12 m, so, if A is the current area, A=18*12

Twice the area would be 2A and it is to be accomplished by adding the same amount, say x, to both dimensions. In symbols, that is:

2A = (18+x) * (12+x)

But we know A is 18*12, so

2(18*12) = (18+x) * (12+x) ; doing the arithmetic

432 = (18+x) * (12+x) ; doing the multiplication using FOIL (first, outside, inside, last)

432 = 18*12 + 18x +12x + x*x ; simplying

432 = 216 + 30x + x*x ; or

0 = -216 + 30x + x*x : or

x*x + 30x -216 = 0 ; using the quadratic equation (or factoring)

(x-6) (x+36) = 0

This has two solutions, 6 and (-36). Since a negative number doesn't make sense in this case, the answer is to add 6m to each side.

Check (18+6) (12+6) = ?

24 * 18 = ?

432 , which is indeed twice the original area of 216 ( = 18*12)

Twice the area would be 2A and it is to be accomplished by adding the same amount, say x, to both dimensions. In symbols, that is:

2A = (18+x) * (12+x)

But we know A is 18*12, so

2(18*12) = (18+x) * (12+x) ; doing the arithmetic

432 = (18+x) * (12+x) ; doing the multiplication using FOIL (first, outside, inside, last)

432 = 18*12 + 18x +12x + x*x ; simplying

432 = 216 + 30x + x*x ; or

0 = -216 + 30x + x*x : or

x*x + 30x -216 = 0 ; using the quadratic equation (or factoring)

(x-6) (x+36) = 0

This has two solutions, 6 and (-36). Since a negative number doesn't make sense in this case, the answer is to add 6m to each side.

Check (18+6) (12+6) = ?

24 * 18 = ?

432 , which is indeed twice the original area of 216 ( = 18*12)

Sep 26, 2010 | Vivendi Excel@ Mathematics Study Skills...

U shouldnt have a lot of issues, some bugs but im sure they wont be often.
Most of the upgrades were bug fixes.

Nov 02, 2009 | Apple Educational & Reference Software

1.2c 2.x 3.8ac 4 .2ac 5.12r...hope these answers are helpful to you..

Jun 22, 2009 | Vivendi Excel@ Mathematics Study Skills...

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