Finding the roots of quadratic equations

x(x-4) = 0
1. x=0
2. x-4=0 which means x=4
3. OR
3x^2 - 7 = 0
1. Manipulate the equation so x^2 = 7/3
2. therefore x= +/- sq root 7/3
x^2-10x+21=0
1. cross method if possible
2. (x-7)(x-3)=0
3. x-7=0 ...x=7
4. OR
5. x-3=0 ...x=3
When all else fails, use the quadratic equation
1. Remember the coefficients are substituted NOT the terms
2. Don't be lazy ... Formula line, Substitution line, then start to work it out
Completing the square
1. halve the x term & square it
2. add it to both sides of the eqation
3. then it becomes something like the method in the centre top
4. manipulate the equation so coeffient of x^2 is +1

Resumo de Recurso

	Criado por fiona.pain aproximadamente 13 anos atrás