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3 years ago
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Isadore Quitzon
1 Answer
Enthusiastic, Patient, Maths Teacher with 30 Years Experience.
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Equations with x2 in them are called quadratics. There are three methods for solving quadratic equations.
The first is to factorise it if possible
E.g. x2+3x+2 = 0 becomes (x+2)(x+1)=0.
Since one of these brackets must be worth zero to get the zero on the left-hand side then
either x+2=0 or x+1=0
so x=-2 or x=-1
You can also use the quadratic formula, which is useful if your equation will not factorise.
So if ax2+bx+c=0 then
x=
So if x2+3x+2 = 0 then here a=1, b= 3 and c=2. You then substitute these values into the formula using your calculator to find your answer.
Yet a further method is to complete the square.
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