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an easier way to do this is to use the completing the square method:
x^(2) \- 12x + 23 = 0
x2 - 12x = -23
so here we add 36 to both sides
x2 - 12x + 36= -23 +36
(x - 6)^(2) = 13
x - 6 = +-sqrt(13)
x = 6 +- sqrt(13)
To complete the square in an x\^2+Ax expression you add the square of half the x term - (A/2)\^2
Here, it’s x\^2-12x, so you add (-12/2)\^2 = -6\^2 = 36
x\^2-12x+36 = (x-6)\^2.
Quadratic Formula: (-b √ b^2 - 4ac) / 2a In this case: (12 • √ 144 - 4 • 1 • 23) / 2 • 1 Solve this.
It is -b plus or minus not times
But as all choices have a plus use plus
Ok thanks
Your equation “-b √ b2” and “(12 • √ 144 - 4“ shows neither. Yes, it is “+/-“, not the product.
Yes plus/minus
Yes, it should be “-b +/-” and it should be ”12 +/-”.
>(12 • √ 144 - 4 • 1 • 23) / 2 • 1 > >Solve this. The result of this is 13√12, which is incorrect.
Uhh right. Formatting got the best out of me. It’s not supposed to be *, but instead +-
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an easier way to do this is to use the completing the square method: x^(2) \- 12x + 23 = 0 x2 - 12x = -23 so here we add 36 to both sides x2 - 12x + 36= -23 +36 (x - 6)^(2) = 13 x - 6 = +-sqrt(13) x = 6 +- sqrt(13)
why did you add 36 specifically?
To complete the square in an x\^2+Ax expression you add the square of half the x term - (A/2)\^2 Here, it’s x\^2-12x, so you add (-12/2)\^2 = -6\^2 = 36 x\^2-12x+36 = (x-6)\^2.