Question

Which of the following equations has only one solution?

x^2 - 8x + 16 = 0
x(x - 1) = 8
x^2 = 16

Answer 1

x^2-8x+16=0

Answer 2

put them in standard form and calculate b^2-4ac
if it is zero, then the equation has only one solutions (actually two equal roots)

Answer 3

the first one
quadratic formula

Answer 4

\[-(-8)\pm \sqrt{(-8)^{2}-4(16)}\over 2\]\[8\pm \sqrt{0}\over 2\]

Answer 5

i guess we do not have to actually calculate the roots for this question....
just calculating b^2-4ac will give us the answer....

Answer 6

You can also factor the first one...you'll get (x-4)(x-4)=0 and x can only equal 4

Answer 7

True, but was just checking it out, what does a discriminate = zero signify?

Answer 8

Only one solution. (Because there's only one square root of zero).

Answer 9

if D = 0, two equal roots i.e we can say one solution
if D>0, two distinct real roots
if D<0, imaginary roots

Answer 10

Yes, my book says one (repeated) solution, but in this problem, I don't see a repeated solution, do you?

Answer 11

How come nobody is helping Nicolette?

Answer 12

just get a ti 84 plus and it will do it for you

Answer 13

I guess when it is identical it is difficult to discern lol

Answer 14

see it says two roots in the sense

(8+0)/2 and (8-0)/2
but both result in 4.... so one solution

Answer 15

Because he/she is posting boring financial questions.

Answer 16

lol

Answer 17

Have a nice day all.

Answer 18

same to u radar.....

Answer 19

a

Answer 20

\[x ^{2}-8x+16\]