Week 7 – Math 10

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This question stumped me for a very long time, since it had multiple parts that weren’t all trigonometry. For example, I was not sure if I had to use the distance over time triangle from physics, or if I should use unit analysis from the measurement unit. I tried many different things, and I finally found out how to solve the problem!

At first I used sine to figure out the length of the hypotenuse, but later on as I thought about it, I realized it would not make sense. The biker is going along a highway, it’s impossible to travel along the hypotenuse side! So I changed the equations:

tan 8 = \frac{60}{x}

\frac{60}{tan 8} = 426.92

\frac{426.92 km}{20 s}={x km}{1 hr}

I multiplied 20s by 3 into 60s, which is 1 minute. Then I multiplied it by 60 to convert it into 1 hour. You must do the same to the top numbers, so I got an answer of:

426.92\cdot 30\cdot 60 = 76.84

So the average speed the biker travelled at is 77km/hr!

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