How do you solve (2x-1)(x+3)=0?

2 Answers
Tony B
Mar 16, 2016

x=1/2" or "x=-3

Explanation:

For this equation to become the value of zero it means that either the left bracket is zero or the right bracket is zero.

'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Consider color(blue)((2x-1)=0)

color(magenta)("Detailed calculation to show how it works")

Add color(red)( 1) to both sides

" "color(blue)(2x-1color(red)(+1)=0color(red)(+1))

" "color(blue)(2x+0=1)

Divide both sides by color(red)(2)

" "color(blue)(2/(color(red)(2))xx x=1/(color(red)(2))

But 2/2 = 1 giving

x=1/2

'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Consider color(blue)((x+3)=0)

color(magenta)("Calculation skipping steps")

x=-3
'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

BRIAN M.
Mar 16, 2016

x can equal -1/2 or -3

Explanation:

(2x-1)(x+3)=0

To solve for the value of x simply take each of the binomial factors and set them equal to zero.

2x+1 = 0
2xcancel(+1)cancel-1 = 0-1
(cancel2x)/cancel2 =-1/2
x=-1/2

x+3 = 0
xcancel(+3)cancel-3 = 0-3
x=-3

x can equal -1/2 or -3

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