Question 712445
distance = rate x time


one plane
rate = 550
time = t
distance = 550t


other plane
rate = 500
time = t
distance = 500t


When will their combined distances equal 2100


550t + 500t = 2100   {added distances and set equal to 2100}
1050t = 2100 {combined like terms}
t = 2 {divided each side by 1050}


In 2 hours they will be 2100 mi. apart
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