Answer: 1.8x - 4
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Step-by-step explanation:
Subtract the two expressions
Tomas - Angie = (3x) - (1.2x+4) = 3x - 1.2x-4 = 1.8x-4
This represents how many more miles Tomas jogged compared to Angie.
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A more concrete example would be to say hypothetically
Tomas = 10 miles
Angie = 4 miles
So Tomas - Angie = 10-4 = 6 means he jogged 6 more miles than Angie.
That's why we subtracted. The order of subtraction matters. Saying 10-4 is different from 4-10.