D), I believe it is -42. Correct me if im wrong :}
<span>Equation:
train distance + plane distance = 1300 miles
50x + 275x = 1300
x(325) = 1300
x = 4 hours
4x2=8
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The trip took 8 hrs.</span>
10+5x=7x-4
1. simplify 7x - 5x
10=2x-4
2. add four to both sides
10+4=2x
+ 4 4
14=2x
3. divide 14 to both sides
14=2x
x=7
if other experts state the same thing in their own paper or document.
