How do you do (x-5) (x-1)=0 ?

We can use the zero product property, i.e. since the product of these two expressions is 0, at least one of them must be 0. So we can write 

x-5=0 or x-1=0 

which means x=5 or x=1 


:)

How do you solve (x-4)(x+8)=0

We can use the zero product property: 

(x-4)(x+8)=0 means 
x-4=0 or x+8=0 

so that x=4 or x=-8 



:)

Factoring Quadratics expressions,

Factoring quadratics usually gives students headaches, bu it does not have to be this way. Let's go over some facts that will help us. 

• Not every quadratic can be factored into binomials (unless you factor over the complex numbers) 
• Factoring may be sometimes called finding the zeros, or solving for x
• Special factoring identities are very useful - so try them first
• There are several valid factoring methods but they all depend on finding a pair of factors of the product of the coefficients a and c and that add to the coefficient b 

I have been posting several factoring examples, look for them under the labels factoring, factoring polynomials, factoring quadratics, etc.