week 6 precalc

this week in precalc 11 we learned how to find X with this new formula we were shown.

$x=\frac{-b \pm\sqrt {b^2-4ac} } {2a}$

the way the question will be set up for you to use this formula is like

$x^2 +x +n = 0$

it is very important that it = 0 because if it doesn’t than you will get the wrong answer

so for our example we will have

$x^2 +8x +5 = 0$

$x^2$ =a 8x=b 5=c

$0=\frac{-8 \pm\sqrt {8^2-4(1)(5)} } {2(1)}$

now you just have to follow the rules pedmas

$0=\frac{-8 \pm\sqrt {64-20} } {2}$

$0=\frac{-8 \pm\sqrt {44} } {2}$

$0=\frac{-8 +or- 4\sqrt {11} } {2}$

$0=-4 +or- 2\sqrt {11}$

x= $-2\sqrt {11}$ if +2

x= $-6\sqrt {11}$ if -2

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