how do you factor x^2 + 7x + 12.25
2007-08-02 08:38:30 · 6 answers · asked by K 4 in Science & Mathematics ➔ Mathematics
(x+7/2)(x+7/2)
2007-08-02 08:47:19 · answer #1 · answered by Anonymous · 1⤊ 0⤋
Make 12.25 a fraction first. You know .25 is 1/4 so your fraction is going to be 49/4. Now, you take the square root of 49/4 because when you factor it out, you want the sum of it to be 7. So the square root of 49/4 is 7/2 (square root of 49 is 7 and 4 is 2). Now just plug them in.
(x+7/2)(x+7/2)
2007-08-02 15:45:33 · answer #2 · answered by Alexis P 2 · 0⤊ 0⤋
Change 12.25 into 12 1/4 = 49/4
Factor into (x+7/2)(x+7/2)
If you prefer decimals in the answer, that is (x+3.5)(x+3.5)
2007-08-02 15:41:53 · answer #3 · answered by jenh42002 7 · 1⤊ 0⤋
(4x^2 + 28x + 49)/4
Notice the first and third terms are perfect squares,
they are squares of 2x and 7, so we look at
2*2x*7 to see if it equals the middle term,
and it does, so we have a perfect square
[(2x +7)^2]/4
= (x + 3.5)^2
In fact I should have seen this at the outset,
because x^2 and 12.25 are both squares, squares of
x and 3.5.
And 2*x*3.5 = 7x, the middle term.
2007-08-02 15:44:30 · answer #4 · answered by Hy 7 · 0⤊ 0⤋
the factors of 12.25 have to add up to 7
at least one of these is going to have to be a decimal number...thus causing both to be decimal numbers
make a list
.5 and 6.5
1.5 and 5.5
etc.
multiply them together
factored and simplfied you should get (x + 3.5)^2
2007-08-02 15:44:10 · answer #5 · answered by lizzyhappy2007 2 · 0⤊ 0⤋
(x+3.5)(x+3.5)= (x+3.5)^2
2007-08-02 15:41:35 · answer #6 · answered by Anonymous · 0⤊ 0⤋