Write a system of equations to describe the situation below, solve using elimination, and fill in the blanks.To keep in shape, Danny exercises at a track near his home. He requires 34 minutes to do 9 laps running and 4 laps walking. In contrast, he requires 40 minutes to do 10 laps running and 5 laps walking. Assuming he maintains a consistent pace while running and while walking, how long does Danny take to complete a lap?Danny takes _____ minutes to run a lap and _____ minutes to walk a lap.
Q. Write a system of equations to describe the situation below, solve using elimination, and fill in the blanks.To keep in shape, Danny exercises at a track near his home. He requires 34 minutes to do 9 laps running and 4 laps walking. In contrast, he requires 40 minutes to do 10 laps running and 5 laps walking. Assuming he maintains a consistent pace while running and while walking, how long does Danny take to complete a lap?Danny takes _____ minutes to run a lap and _____ minutes to walk a lap.
Define Equations: Let's denote the time Danny takes to run a lap as r minutes and the time he takes to walk a lap as w minutes. We can then write two equations based on the information given:For 9 laps running and 4 laps walking taking 34 minutes: 9r+4w=34For 10 laps running and 5 laps walking taking 40 minutes: 10r+5w=40
Use Elimination Method: To use elimination, we want the coefficients of one of the variables to be the same (or opposites) in both equations. We can multiply the first equation by 5 and the second equation by 4 to get the coefficients of w to match:(9r+4w)×5=34×5(10r+5w)×4=40×4
Multiply Equations: After multiplying, we get the new system of equations:45r+20w=17040r+20w=160
Eliminate Variable: Now we can subtract the second equation from the first to eliminate w:(45r+20w)−(40r+20w)=170−160
Solve for r: This simplifies to: 5r=10
Substitute r: Dividing both sides by 5 to solve for r gives us:r=510r=2So, Danny takes 2 minutes to run a lap.
Solve for w: Now we can substitute r=2 into one of the original equations to solve for w. We'll use the first equation:9r+4w=349(2)+4w=34
Solve for w: Now we can substitute r=2 into one of the original equations to solve for w. We'll use the first equation:9r+4w=349(2)+4w=34 This simplifies to:18+4w=34
Solve for w: Now we can substitute r=2 into one of the original equations to solve for w. We'll use the first equation:9r+4w=349(2)+4w=34 This simplifies to:18+4w=34 Subtracting 18 from both sides gives us:4w=34−184w=16
Solve for w: Now we can substitute r=2 into one of the original equations to solve for w. We'll use the first equation:9r+4w=349(2)+4w=34 This simplifies to:18+4w=34 Subtracting 18 from both sides gives us:4w=34−184w=16 Dividing both sides by 4 to solve for w gives us:w0w1So, Danny takes 4 minutes to walk a lap.
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