Im wondering how i would go about solving this... 2x^2+9x+4
Please can you go through the steps?
Please can you go through the steps?
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I'm guessing you want the roots:
(2x+1)(x+4) = 0
2x + 1 = 0
x = -0.50
x + 4 = 0
x = -4
(2x+1)(x+4) = 0
2x + 1 = 0
x = -0.50
x + 4 = 0
x = -4
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Obviously you want the statement above to = 0, or you couldn't solve it.
2x² + 9x + 4 = 0
When solving a quadratic, you usually end up with 2 () like this
( )( ) = 0
The first term of each must multiply together to give you the x² term in your equation, in your case they are most likely 2x & x
(2x )(x ) = 0
Since all three terms in your problem are positive, we know there won't be any negative signs, so now we are at
(2x + )(x + ) = 0
The last terms must multiply together to get your last term, 4. So they are most likely 1 & 4, or 2 & 2, or maybe 8 & 1/2, etc. They must also make it so when you multiply the whole thing out, you end up with your original equation. The 2x makes this tricky, but playing around you can get
(2x + 1)(x + 4) = 0
You can see when you multiply them together you get 2x*x + 2x*4 + 1*x + 1*4 = 2x² + 8x + x + 4 = 2x² + 9x + 4.
You didn't ask for the answer, but for (2x + 1)(x + 4) = 0 to be true, x = -1/2 or -4.
2x² + 9x + 4 = 0
When solving a quadratic, you usually end up with 2 () like this
( )( ) = 0
The first term of each must multiply together to give you the x² term in your equation, in your case they are most likely 2x & x
(2x )(x ) = 0
Since all three terms in your problem are positive, we know there won't be any negative signs, so now we are at
(2x + )(x + ) = 0
The last terms must multiply together to get your last term, 4. So they are most likely 1 & 4, or 2 & 2, or maybe 8 & 1/2, etc. They must also make it so when you multiply the whole thing out, you end up with your original equation. The 2x makes this tricky, but playing around you can get
(2x + 1)(x + 4) = 0
You can see when you multiply them together you get 2x*x + 2x*4 + 1*x + 1*4 = 2x² + 8x + x + 4 = 2x² + 9x + 4.
You didn't ask for the answer, but for (2x + 1)(x + 4) = 0 to be true, x = -1/2 or -4.
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Right 'old boy' let's see just what we have here ?
2x^2 + 9x + 4 Well 2x^2 is really 2x times x and 4 is 4 times 1
therefore 2x times 4 gives 8x and the other part is x times 1 gives x
therefore to get the middle term 9x we need to ADD 8x and x
so obviously the factors must be 2x + 1 and x + 4
hence 2x^2 + 9x + 4 is (2x + 1) ( x + 4 )
Good bye !!
2x^2 + 9x + 4 Well 2x^2 is really 2x times x and 4 is 4 times 1
therefore 2x times 4 gives 8x and the other part is x times 1 gives x
therefore to get the middle term 9x we need to ADD 8x and x
so obviously the factors must be 2x + 1 and x + 4
hence 2x^2 + 9x + 4 is (2x + 1) ( x + 4 )
Good bye !!