Key Numbers of Inequality...2

[nycmathguy]

Section 2.7
Question 10

9x^3 - 25x^2 ≤ 0

(x^2)(9x - 25) ≤ 0

Set each factor to zero & solve for x.
Replace ≤ with the equal sign.

x^2 = 0

sqrt{x^2} = sqrt{0}

x = 0

9x - 25 = 0

9x = 25

x = 25/9

The key numbers are x = 0 and x = 25/9.

You say?

 

[MathLover1]

correct

 

[nycmathguy]

correct

I'm really cooking with gas now.

 

[nycmathguy]

correct

Diagonals of Parallelogram

 

[MathLover1]

tired now, tomorrow

 

[nycmathguy]

tired now, tomorrow

Ok. Remember, you are not obligated to answer all my questions in one day. Feel free to stretch your reply throughout the week. We are not rushing through precalculus. If you ever fell like taking a break from math, let me know.