SOLUTION: HELP a)solve 4x^2=12 I have to find x for this one b)Find the intercepts of f(x)=4x^2-12 I am totally lost on this Thanks

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: HELP a)solve 4x^2=12 I have to find x for this one b)Find the intercepts of f(x)=4x^2-12 I am totally lost on this Thanks      Log On


   

Question 142921: HELP
a)solve 4x^2=12 I have to find x for this one
b)Find the intercepts of f(x)=4x^2-12
I am totally lost on this
Thanks
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
a) Solve for x:
4x%5E2+=+12 Divide both sides by 4.
x%5E2+=+3 Now take the square root of both sides.
x+=+sqrt%283%29 or x+=+-sqrt%283%29
b) Find the zeros of:
f%28x%29+=+4x%5E2-12 Finding the zeros of this quadratic equation means find the values of x where the parabola intercepts the x-axis, and, of course, at these points, y = 0 or f(x) = 0, so...
0+=+4x%5E2-12 Add 12 to both sides.
12+=+4x%5E2 Divide both sides by 4.
3+=+x%5E2 Take the square root of both sides.
x+=+sqrt%283%29 or x+=+-sqrt%283%29