<ABD and <EBC are equal to each other. In order to solve for the x value, set the equations equal to each other;
4x = 2x + 40,
x = 20
Based off what angle you are trying to find, you would plug x = 20 into the equation.
The first thing to do is organize all the given data so that you won't be confused which is which. Let's denote all the given that belongs to the marathon runner with a subscript of 1 and that of the trackman with a subscript of 2. The first equation we could do is find the sum of time:
t₁ + t₂ = 3 hours and 1 minute
For consistency, let's convert minute to hours.
1 minute (1 hour/60 minutes) = 1/60
Total time = 3+1/60 = 3.0167 hours
t₁ + t₂ = 3.0167 hours ----> equation 1
The other equation is the total distance. When you multiply speed with time, the answer would be distance. Thus.
9t₁ + 12t₂ = 28 miles ----> equation 2
Since there are two unknowns and 2 equations, the system is solvable:
t₁ = 3.0157 - t₂
9(3.0167 - t₂) + 12t₂ = 28
t₂ = 0.2832 hour, and
t₁ = 3.0157 - 0.2832 = 2.733 hours
Therefore, the distance run by the marathon runner is
9*2.733 = 24.597 or approximately 24 3/5.
161
7*18 + 5*7
126 + 35 =
161
