Intercepts

In the first part of the last question, we are simply being asked to find the \(x\)-intercepts. To do so, we let \(y=0\):

[MATH]-0.23x^2+1.87x+1.5=0[/MATH]
And then solve for \(x\). I'd begin by multiplying through by -100, so clear the decimals and get rid of the leading negative sign:

[MATH]23x^2-187x-150=0[/MATH]
Next, apply the quadratic formula...what do you get?
it going to be
X= 187+-radical48769/46
is that right?
 
In the first part of the last question, we are simply being asked to find the \(x\)-intercepts. To do so, we let \(y=0\):

[MATH]-0.23x^2+1.87x+1.5=0[/MATH]
And then solve for \(x\). I'd begin by multiplying through by -100, so clear the decimals and get rid of the leading negative sign:

[MATH]23x^2-187x-150=0[/MATH]
Next, apply the quadratic formula...what do you get?

sorry my post are replying twice
 
Which of the roots is the missile's final \(x\)-coordinate? What is the missile's initial \(x\)-coordinate?
 
Which of the roots is the missile's final \(x\)-coordinate? What is the missile's initial \(x\)-coordinate?

Sorry mark but i can not understand the last question i have to roots one is positive one is negative

what do i need to do exactly ?
 
As I mentioned before, we are assuming that the launch of the missile coincides with \(x=0\), so we can disregard the negative root. So, the final position is at the positive root, and the initial position is at \(x=0\).

Here's a diagram:

fmh_0077.png

To find the total horizontal distance traveled, subtract the initial \(x\)-coordinate from the final one. What do you get?
 
As I mentioned before, we are assuming that the launch of the missile coincides with \(x=0\), so we can disregard the negative root. So, the final position is at the positive root, and the initial position is at \(x=0\).

Here's a diagram:

View attachment 13630

To find the total horizontal distance traveled, subtract the initial \(x\)-coordinate from the final one. What do you get?

is it 9 ?
i am really sorry if i make so many mistakes
 
No, it is:

[MATH]\Delta x=\frac{187+\sqrt{48769}}{46}-0=\frac{187+\sqrt{48769}}{46}\approx8.87[/MATH]
 
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