INEQUALITIES B9

If 10x + 21 ≥ 7 + 3x ≥ 9x – 10; find x.

Solution

10x + 21 ≥ 7 + 3x and  7 + 3x ≥ 9x - 10

10x – 3x ≤ 7 - 21 and  7 +10 ≤ 9x - 3x

7x ≤ -14 and  14 ≤ 6x 

7x ≤ -14  and  17 ≤ 6x

7        7            6      6

x ≤ -2 and  ¹⁷/6 ≤ x

x ≤ -7 and  x  ≥ ¹⁷/6

TRY THIS…………….

If 10x + 4 ≥ 7 + 3x ≥ 9x – 53; find x