Question

ten times the square of a nonzero number is equal to eitghty times the number. what is the number?

Answer 1

Can you write an equation out of this? It will help you.

Answer 2

^ Yup.

Answer 3

Hey there!

Let the non-zero number be \(\sf x\), then according to the question,

\(\sf 10 \times x^2 = 80 \times x\)

Now solve the equation to find the value of \(\sf x\)

Answer 4

good set up, cookielate.
BUT by dividing by x, you lose solutions

Answer 5

well, if your condition is that \(\large\color{black}{ \displaystyle x>\bf 0 }\), but I didn't see that.

Answer 6

my replies got mixed up-:(

Answer 7

8 was correct. you guys have no idea ho much yall helped thank you so much

Answer 8

anyway,
\(\large\color{black}{ \displaystyle10x^2 = 80x }\)
\(\large\color{black}{ \displaystyle10x^2 - 80x=0 }\)
\(\large\color{black}{ \displaystyle x^2 - 8x=0 }\)
\(\large\color{black}{ \displaystyle x(x-8)=0 }\)

yes, ultimately you come to one answer only though, as it says that x is a none zero number.

and the constant "c" is not there, so you took a "shortcut" cutting it out, knowing that 0 will be a solution of a quadratic.

Answer 9

I was going to medal that reply, because it is eventually correct... and youerased it... dky

Answer 10

How about this?

\(\huge \tt 10x^2 =80x \\ \huge \frac{10x^2}{x}=80 \\ \huge 10x=80 \\ \huge \Rightarrow x=8\)

Answer 11

I am perfectly fine with that!

you can divide by x, yes, because the solution you are losing is 0, but the problem already told us that \(\large\color{black}{ \displaystyle x \ne 0}\)

Answer 12

(but, in other cases don't cancel out the x like this)