According to the vertex and the directrix of the given parabola, the equation is:
The equation of a quadratic function, of vertex (h,k), is given by:
In which a is the leading coefficient.
The directrix is at y = k + 4a.
In this problem, the vertex is (1,4), hence:
The directrix is at y = 7, hence:
Hence, the equation is:
More can be learned about the equation of a parabola at brainly.com/question/26144898
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Answer:
2) 3 pages per hour
3) 4/29 km per minute
Step-by-step explanation:
Division by a fraction is the same as multiplication by the inverse of that fraction.
<h3>2) </h3>
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<h3>3) </h3>
Step-by-step explanation:
We want to find two things-- the speed of the boat in still water and the speed of the current. Each of these things will be represented by a different variable:
B = speed of the boat in still water
C = speed of the current
Since we have two variables, we will need to find a system of two equations to solve.
How do we find the two equations we need?
Rate problems are based on the relationship Distance = (Rate)(Time).
Fill in the chart with your data (chart attached)
The resulting speed of the boat (traveling upstream) is B-C miles per hour. On the other hand, if the boat is traveling downstream, the current will be pushing the boat faster, and the boat's speed will increase by C miles per hour. The resulting speed of the boat (traveling downstream) is B+C miles per hour. Put this info in the second column in the chart. Now plug it into a formula! <u>Distance=(Rate)(Time) </u>Now solve using the systems of equations!
