Help me with Plotting the graph of a function

[ishee099232]

Hello guys, I am having trouble stating the horizontal axis where the curves cut. The coordinates I have found were (-1,2),(1,0), but it is wrong and I cannot figure out how they got the answer (-0,7,0) and (1,0,0) horizontal line coordinates. Please help me and thank you. I am fine with the vertical axis.

 

[R.M.]

"I am having trouble stating the horizontal axis where the curves cut."

That's another way of saying 'find the x-intercepts'. At an x-intercept, the value of y = 0, so your solution of (-1, 2) definitely doesn't work. To find both x-intercepts, set f(x) = 0, and solve. What kind of function is f(x)? How can you solve such a function?

 

[Steven G]

Hi, How can we help you if you do not show us your work so we can see where you made your mistake? So please post back with your work and then we get started helping you.

 

[ishee099232]

"I am having trouble stating the horizontal axis where the curves cut."

That's another way of saying 'find the x-intercepts'. At an x-intercept, the value of y = 0, so your solution of (-1, 2) definitely doesn't work. To find both x-intercepts, set f(x) = 0, and solve. What kind of function is f(x)? How can you solve such a function?

Please show me how you would calculate it. It confusing to understand.

 

[tkhunny]

There is a lovely hint in your table.
x = 1
f(x) = 0

What can we do with that?

 

[Deleted member 4993]

Please show me how you would calculate it. It confusing to understand.

Do you know:

How to calculate roots of quadratic equations?

If you do not remember - please review https://www.purplemath.com/modules/solvquad.htm

If you still have question/s, please tell us exactly where do you get lost.

 

[ishee099232]

There is a lovely hint in your table.
x = 1
f(x) = 0

What can we do with that?

f(1) = 4(1)^2-(1)-3=0
ans = (1,0)
What about this

 

[tkhunny]

f(1) = 4(1)^2-(1)-3=0
ans = (1,0)
What about this

1) Isn't that where it hits the x-axis?
2) You can use this information to find the other location.

 

[Deleted member 4993]

f(1) = 4(1)^2-(1)-3=0
ans = (1,0)
What about this

Please re-read your Original Post - what were you supposed to FIND? Specially re-read part(a).

 

[ishee099232]

I was meant to find the horizontal line coordinates from where the curve cuts on the graph.
Honestly I cannot find the solution. I try using what you mention and I am still struggling. I am more confused then before. I tried the f(x) and x =1 and still did not find the horizontal axis coordinates.

 

[ishee099232]

1) Isn't that where it hits the x-axis?
2) You can use this information to find the other location.

I dont know how to find the other location. To be honest I cant seem to understand how the coordinates have two digitals and the answer to the question has three digits. I am so lost.

 

[Deleted member 4993]

I dont know how to find the other location. To be honest I cant seem to understand how the coordinates have two digitals and the answer to the question has three digits. I am so lost.

How is that - one the answers are (-0.7 , 0) Please explain.

 

[ishee099232]

How is that - one the answers are (-0.7 , 0) Please explain.

This is the answer they gave. I compared it to mine and mine was wrong. I cant seem to figure out what is wrong with my answer.

 

[Deleted member 4993]

I dont know how to find the other location. To be honest I cant seem to understand how the coordinates have two digitals and the answer to the question has three digits. I am so lost.

To be able to do these types of problems you should study "quadratic functions" from your text-book or review:

https://www.purplemath.com/modules/solvquad.htm

It does not look like you have done that!

 

[Deleted member 4993]

This is the answer they gave. I compared it to mine and mine was wrong. I cant seem to figure out what is wrong with my answer.

What was your answer?

 

[ishee099232]

What was your answer?

= (4x+3) (x-1)
answer = x = -3,1

x= -3
f(-3)= 4(-3)^2-(-3)-3
answer = (-3,36)

x = 1
f(1) = 4(1)^2-(1)-3=0
answer = (1,0)

 

[Deleted member 4993]

= (4x+3) (x-1)..................................Correct

answer = x = -3,1 ........................ Incorrect

How did you get those values for x?

 

[ishee099232]

C
check my updated answer

 

[Deleted member 4993]

C

check my updated answer

I did - but please show me how you got x = -3

 

[ishee099232]

I did - but please show me how you got x = -3

Change the positive 3 to -3.