A cyclist rides at a constant speed of 15 miles per hour. At this speed, about how long would it take the cyclist to ride from Frederick, MD to Baltimore, MD?

answer: (3,11) is your answer.

let x and 400 - x be the two numbers.  

==> 0.80x + 0.85(400 - x) = 400 - 68 from the statement of the problem.  

< ==> 0.80x + 0.85(400 - x) = 400 - 68  

==> 340 - 0.05x = 332  

< ==> -0.05x = -8 ==> x = 160, the first number ==> 400 - x = 240, the second number.

answer: qc and de are congruent

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