This could be wrong but the answer should be 4
<span> x/3-2=7
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SImplify
1/3x - 2 = 7
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add 2 to each side
1/3x - </span><span><span>2 </span>+ 2 </span>= <span>7 + <span>2
1/3x = 9
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Multiply each side by 3
3 * (1/3x) = 3 * 9
x = 27</span></span>
Answer:
Terrance would run 20/4 of a mile or 5 miles
Step-by-step explanation:

The last two steps are just me reordering it so it's in standard form.