Answer:
see below
Step-by-step explanation:
19. -9 x = -117
20. -¹/₈ x = -³/₄
21. ⁵/₆ x = -⁵/₉
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19.
x = 117 / 9
x = 13
20.
x = ³/₄ divide ¹/₈
x = 6
21.
x = -⁵/₉ divide ⁵/₆
x = -²/₃