Use the discriminant to determine whether the following equations have solutions that are: two different rational solutions; two different irrational solutions; exactly one rational solution; or two different imaginary solutions.
x2 = -4x – 4

Question

anonymous · Answer

im not sure hahaha... sorry ._."

radar · Answer

The discriminant is the value of$$b ^{2}-4ac$$
Do you know what the values of a, b, c are?

anonymous · Answer

no sorry. never done a problem like this before

radar · Answer

well a is the coefficient of the x^2
b is the coefficient of x
c is the numerical constant
your equation is:$$x ^{2}=-4x-4$$

anonymous · Answer

ok.

radar · Answer

I am going to rearrange the equation so that appears.$$x ^{2}+4x+4=0$$
I added 4x+4 to both sides.  This is legal as I did it to both sides of the equal sign.
Do you follow that?

anonymous · Answer

yes

radar · Answer

a=1
b=4 
c=4

radar · Answer

discriminant is
$$1^{2}-(-4)(1)(4)=1+16=17$$

anonymous · Answer

ok. proceed

radar · Answer

Now the important partl. 

If discriminant is positive, there are two real solutions.
If ther discriminant is 0, there is one repeated solution.
If the discriminant is negative there are no real solutions.

Which category did the discriminant for your equation fit ?

radar · Answer

Hold on a minute, i messed up$$4^{2}-4(1)(4)=16-16=0$$

anonymous · Answer

ther are two real solutions

radar · Answer

That was before I corrected the values for the discriminant which now equals 0

radar · Answer

There is one repeated solution.

the equation can be factored
(x+2)(x+2)=0
x=-2
x=-2

see one repeated solution.

radar · Answer

Sorry about the error, but it was noted before closing this thread.
good luck in your studies.

anonymous · Answer

geekgirl1988, what grade are you in? So that we can help accordingly