Solving inequality is very like solving equation. The only difference: if divide or multiply both sides of
inequality by negative number, we have to change sign of inequality to opposite.
~~~~~~~~~~
5x + 8 ≥ 3x + 8
 8  8
 5x ≥ 3x
 3x  3x
 8x ≥ 0
÷( 8) ÷( 8)
x ≤ 0 , or all real numbers out of interval ( ∞, 0]
<=========•———————>
 ∞  10 0 10 + ∞
Let's verify the answer:
for x = 10,
5 × (10) + 8 ≥ 3 × ( 10) + 8
50 + 8 ≥ 30 + 8
42 ≥  22 (True)
for x = 10,
 5 × 10 + 8 ≥ 3 × 10 + 8
 50 + 8 ≥ 30 + 8
 42 ≥ 38 (False)
10/24/2013

Nataliya D.
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