4. Trigonometry
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Create an equation using the definition of the sine of an angle.
≈ 80 ft
Let's begin with recalling the definition of the sine of an angle. If△ ABCis a right triangle with acute∠A, then the sine of∠Ais the ratio of the length of the leg opposite∠Ato the length of the hypotenuse.
Next, we can write that the sine of 55^(∘) is the ratio of the length of the opposite leg, h, to the length of the hypotenuse, 98. sin 55^(∘)=h/98 We can solve for h by evaluating sin 55^(∘) using a calculator.
LHS * 98=RHS* 98
Rearrange equation
Use a calculator
Multiply
Round to nearest integer
The height of the roller coaster when it reaches the top of the first hill is about 80 feet.