Please help me with this, Thank You.
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Answer:
missing side is 5x - 4
Step-by-step explanation:
x - 1 + ( 3x + 6 ) + third side = 9x + 1
x - 1 + 3x + 6 + third side = 9x + 1
4x + 5 + third side = 9x + 1
third side = 9x + 1 - ( 4x + 5 )
third side = 9x + 1 - 4x - 5
third side = 5x - 4