briannacamille briannacamille
  • 11-07-2014
  • Mathematics
Answered

How do you factor this 8x^2+2x-21=0

Answer :

Pulkit
Pulkit Pulkit
  • 11-07-2014
Solve it like this.. 
8x^2+2x-21=0
8x^2 + 14x - 12x -21=0
2x(4x+7) -3(4x+7) = 0
(4x+7)(2x - 3)=0

So factor 1 is 4x +7 =0 
i.e. x=-7/4

Factor 2 is 2x -3 =0
i.e x=3/2
Answer Link
Lilith
Lilith Lilith
  • 11-07-2014
[tex]8x^2+2x-21=0 \\ \\ 8x^2+2x + 12x -12x-21=0\\\\8x^2+ 14x -12x-21=0 \\ \\ 2x(4x+7)-3(4x+7)=0\\\\(4x+7)(2x-3)=0[/tex]

[tex]4x+7=0 \ \ or \ \ 2x-3 =0 \\\\4x=-7\ \ or \ \ 2x=3\\\\x=\frac{-7}{4}\ \ or \ \ x=\frac{3}{2}[/tex]




Answer Link

Other Questions

What is the speed of light
Write the 2digit number that matches the clues My number has a tens digit that is 8 more than the ones digit Zero is not one of my digits
how do you divide 23 into 713
what quadrilateral shape has 45 degrees135 degrees45 degrees and 135 degrees
93687 in commutativeassociativeand identity way
The following are four largest countrys in the world Russia Canada China united states what country located in south america also ranks as one of the ten larges
Simplify and identify and xvalues for which the expression is undefined 4x8 divided by x22x
I would like to pick an animal or plant cell for a 5th grader for school project What should I use and where do I start
0000028 in scientific notation
would a scientist be tell if a person was male or female by examining a skin cell Please descibe