Need help!

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need help on few problems i have test on homeschool if i dont pass i fail so i have cupple :


1)
Solve by factoring
4x*-1= 0

*= 2


2)

Completing the square
4x+2=x*
*=2


3)
the quadratic formula
4+4x=2x*
*=2



4)

______
./ X+2+15 = 11 (show your check)


5)

5 3
----- = ----
4x X-2


6)
1 1 1
5 ---x - 7---- = 9 ----
2 3 2


7)

at 10 am, eve started out at 55 killometers per catch adrienne, who had a one hour head start, If eve wa still 100 kilomerers behind at 6 pm, how fast was adrienne driving?

 

[stapel]

1) Solve 4x² - 1 = 0 by factoring.

This is just a difference of squares. Where are you stuck in applying the formula?

2) Solve 4x + 2 = x² by completing the square.

Of course, you've moved everything over to one side. How far past that step have you gotten in the formulaic procedure for completing the square?

3) Solve 4 + 4x = 2x² by the Quadratic Formula.

Of course, you've moved everything over to one side. How far have you gotten in plugging the numbers into the Formula?

4) Sorry; can't read this, and there are no instructions included anyway.

5) Sorry; can't read this, and there are no instructions included anyway.

6) Sorry; can't read this, and there are no instructions included anyway.

7) I could guess at how to set up this exercise, but I would feel more confident if a corrected version of the exercise, giving the exact text, were available.

if i dont pass i fail

Trivially true.

Please reply with corrections and clarifications, using the formatting explained in the "Forum Help" pull-down menu at the very top of the page. When you reply, please include all of your work. Thank you.

Eliz.

 

[Unco]

4)
  ______
./ X+2+15 = 11 (show your check)

If that radical excludes 15, note that \(\displaystyle \mbox{\sqrt{x+2}}\) cannot be negative, so 15 cannot be brought down to 11.

If that is \(\displaystyle \mbox{\sqrt{x + 17} = 11}\), square both sides and solve for x. Check that value for x gives \(\displaystyle \mbox{\sqrt{x + 17}}\) equal to 11.

5)

  5       3 
----- = ----
 4x      X-2

Multiplying both sides by the lowest common denominator (LCD), \(\displaystyle \mbox{4x(x - 2)}\), (noting that x cannot equal 0 or 2 -- otherwise we have a zero denominator) gives

\(\displaystyle \mbox{ 5(x - 2) = 3(4x)\)

6)
   1       1        1  
5 ---x - 7---- = 9 ----
   2       3        2

Multiplying both sides by the LCD of all the terms, 6, will makes things nicer.

7)

at 10 am, eve started out at 55 killometers per catch adrienne, who had a one hour head start, If eve wa still 100 kilomerers behind at 6 pm, how fast was adrienne driving?

Let A be Adrienne's speed.

Distance travelled = speed * time
(and we're going with constant speeds)

Eve's distance at 6pm = 55 km/hr * (time from 10am to 6pm, in hours)

Adrienne's distance at 6pm = A km/hr * (time from 9am to 6pm, in hours)

And Eve's distance travelled at 6pm is 100km less than Adriene's. Solve for A.