Question 1914: I can't find an example in my book or any where. Please help. Thank you.
X2 (X squared) +7X +6=0
I am supposed to find the Quadratic. Quadratic what?
Thank you.
Answer by longjonsilver(2297)   (Show Source):
You can put this solution on YOUR website! there are tons of examples of these on this website and when you say "my book" do you mean your textbook? If so, it must be a cookery book, since any respecting maths book will have umpteen examples of quadratics. If you meant your notebook...what have you been doing in class to not have examples when this is your homework?
That said...read the following:
 IS the quadratic equation. You need to solve it ie find the value(s) of x where all that is indeed equal to zero. This in essence is asking "if you plot the graph, where does it cross the x-axis?". That is all.
As for how to solve it, well there are 2 main methods
1. factorising which is "convert the equation you have into 2 parts that multiply together. Why do this? Because this equals zero remember and if you have 2 things that multiply together to equal zero then one or the other of them has to be zero
2. using the quadratic formula...THIS IS IN ANY....ANY....ANY maths textbook, so read the bloody thing.
Looking at your equation, it factorises easily, so i will show you that.
Without going into why, as such, look at the last two terms...the 7x and the 6...specifically the 7 and the 6.
We need to find 2 numbers that multiply to equal the 6 and those 2 numbers also add together to give 7
Possibilities?...easy combinations are:
1x6
2x3
Of these only 1 and 6 add to equal 7, so these are the numbers i need.
so we can now say that  can be written as (x+6)(x+1)
so, (x+6)(x+1) = 0, and as i said earlier, written like this, then one or the other thing in brackets must be zero, so
either (x+6) = 0 or (x+1) = 0
which means that the number x must be either -6 or -1.
Only these 2 numbers, when put into the equation will make it equal to zero and if you drew the graph of  , it would cross the x-axis at points x=-6 and x=-1.
ok?
Jon.
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