For which value of x does the graph of y = 3x2 − 2x − 5 cross the x-axis?

−1

−2

-3/5

-5/3

Question

For which value of x does the graph of y = 3x2 − 2x − 5 cross the x-axis?

−1

 −2

-3/5

-5/3

amistre64 · Answer

what is the value of y for all points on the x axis?

anonymous · Answer

Idk

amistre64 · Answer

....  how do we plot a point onto the x axis?

anonymous · Answer

With the point y and x

amistre64 · Answer

correct,  and it would be good to know for future references, that any point on the x axis has a y value of:  0

amistre64 · Answer

so the simplest way you can obtain an answer for this is to find the option that makes y = 0

anonymous · Answer

so i have to substitute the answers into the equation to see which one it is

amistre64 · Answer

yes, the simplest option might be to try x=-1 ...  and see if we can weed it out

anonymous · Answer

ok ill try it real quick

anonymous · Answer

It equals 2 so its not right

amistre64 · Answer

lets try that again shall we

3x2 − 2x − 5
  -1    -1
--------------
 3     + 2    - 5

            5 - 5 = ?

amistre64 · Answer

the double check method (patent pending) is only as good as your worst mistakes :)

anonymous · Answer

Ohhhh I worked the problem out wrong

anonymous · Answer

$$0=3(-1)^2-2(1)-5 $$
this is wat idid

amistre64 · Answer

it happens :)

so, x=-1 makes y=0, good luck

anonymous · Answer

Thank You So Much!!!!! :D