Where My MAth Teachers AT i Need Hellp DAwwg,?

Question

what are the steps for completing the square method and the zero product method. my teacher is a fat lazy ho and all she does is talk about that show lost and her boyfreind. so please help me out i have an 83 and if i can understand this i will do good on the test and bring it up to a 90.. Please Help A BroTha out.

Answer 1

Be nice.

But I will try....

Start with x^2 + 8x -7 = 0

1 Get the constant to the other side of the equation.
x^2 + 8x = 7

2. On the left hand side we want a perfect square trinomial. You can do this by taking the coefficient of the x term...divide it by 2 and square it.
8/2 = 4
4^2 = 16

3. Add this number to both sides of the equation....This is why it is legal.
x^2 +8x +16 = 7+16

4. Simplify both sides.
(x-4)^2 = 23

5. Take the square root of both sides (sqr)

sqr((x-4)^2) = sqr(23)

6. Simplify
x-4 = sqr(23)


7. Solve for x
x = sqr(23) +4

8. Make it look nice and remember the sqr of a number is +/-

x = 4 +/- sqr(23)

The zero product method is what you use when the quadractic equation is factorable. If you have two numbers that are multiplied, only one of them has to be equal to zero.

So, let's say you have factored an equation to
(x-5)(x+9) = 0

If x =5, one of the factors is 0 and the answer would be 0/

Also, if x = -9, the same thing happens.

Good LucK and be nice. It will only help in the long run.