See where it's equal and where it's undefined.
Undefined if x = 0
Cross multiply: x(x - 3) = -x + 8
x^2 - 3x = -x + 8
x^2 - 2x - 8 = 0
(x - 4)(x + 2) = 0
x = 4 or x = -2
This sets up four intervals: x ≤ -2; -2 ≤ x < 0; 0 < x ≤ 4, and x ≥ 4
Test a number in each interval to see if it works in the original. The intervals where it comes out true are your answer. For example, to test x ≤ -2 plug in -3:
(-3 + 8) ÷ -3 ≥ -3 - 3
-5/2 ≥ -6 true
To test -2 ≤ x < 0 try x = -1:
(-1 + 8) ÷ -1 ≥ -1 - 3
-7 ≥ -4 false
(-x+8)/x ≥ (x - 3)
Subtract x - 3 from both sides:
(-x+8)/x - x + 3 ≥ 0
Get a common denominator of x:
(-x+8)/x - x²/x + 3x/x ≥ 0
Combine the numerators:
(-x² - 2x + 8)/x ≥ 0
Factor:
-(x² + 2x - 8)/x ≥ 0
-(x + 4)(x - 2)/x ≥ 0
The important points are are x=-4, x=0, x=2.
The places where the result is ≥ 0 are:
x ≤ -4 or 0 < x ≤ 2
Answer:
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Answers & Comments
See where it's equal and where it's undefined.
Undefined if x = 0
Cross multiply: x(x - 3) = -x + 8
x^2 - 3x = -x + 8
x^2 - 2x - 8 = 0
(x - 4)(x + 2) = 0
x = 4 or x = -2
This sets up four intervals: x ≤ -2; -2 ≤ x < 0; 0 < x ≤ 4, and x ≥ 4
Test a number in each interval to see if it works in the original. The intervals where it comes out true are your answer. For example, to test x ≤ -2 plug in -3:
(-3 + 8) ÷ -3 ≥ -3 - 3
-5/2 ≥ -6 true
To test -2 ≤ x < 0 try x = -1:
(-1 + 8) ÷ -1 ≥ -1 - 3
-7 ≥ -4 false
(-x+8)/x ≥ (x - 3)
Subtract x - 3 from both sides:
(-x+8)/x - x + 3 ≥ 0
Get a common denominator of x:
(-x+8)/x - x²/x + 3x/x ≥ 0
Combine the numerators:
(-x² - 2x + 8)/x ≥ 0
Factor:
-(x² + 2x - 8)/x ≥ 0
-(x + 4)(x - 2)/x ≥ 0
The important points are are x=-4, x=0, x=2.
The places where the result is ≥ 0 are:
x ≤ -4 or 0 < x ≤ 2
Answer:
x ≤ -4 or 0 < x ≤ 2