how do I find the x intercepts of a parabola given by this equation; y = 2xsquared-4x

Question

phi · Answer

you find the x's where y=0
in other words, solve
$$ 2x^2 -4x = 0 $$
I would first divide both sides by 2
then factor x from the two terms on the left

anonymous · Answer

would you do a step by step for  I am not understanding the example in my book

phi · Answer

can you divide both sides by 2 ?  what do you get ?

phi · Answer

yes
x^2 -2x = 0

next factor x from each term to get
x(x-2)=0

phi · Answer

now use this (nifty !) idea:   if A*B =0  then either A=0 or B=0  (or both at the same time are zero)

in other words if you have
x * (x-2) = 0
then it could be  x=0   or  (x-2)=0

what two values make  x(x-2) = 0 ?     clearly x=0 is one
what makes  x-2 = 0  true ?