Math

[A.nicholas]

If a rock falls from a height of 20 meters on earth, the height H in meters after x seconds is approximately H(x)=20-4.9^2
A)what is the height of the rock when x=1 second? X=1.1 second? X=1.2 second? X=1.3seconds?
B) when the height of the rock 15 meters? When is it 10 meters? When is it meters?
C) when does the rock strike the ground?

 

[Romsek]

Welcome to the site. You might want to review submission guidelines.

As it is we await what efforts you've made so far at solving the problem.

 

[Dr.Peterson]

If a rock falls from a height of 20 meters on earth, the height H in meters after x seconds is approximately H(x)=20-4.9^2
A)what is the height of the rock when x=1 second? X=1.1 second? X=1.2 second? X=1.3seconds?
B) when the height of the rock 15 meters? When is it 10 meters? When is it meters?
C) when does the rock strike the ground?

You meant to say H(x)=20-4.9x^2.

For part A, you have to evaluate the function.

For part B, solve equations of the form H(x) = C.

For part C, solve H(x) = 0.

For all of them, we'll want to know where you need help, specifically, including whatever work you are able to do.

 

[Otis]

… x=1 second? X=1.1 second? …

… When is it meters? …

Oops, you omitted the height, from that question.

PS: In math, symbols x and X are different. Please use one or the other to represent the amount of time, not both.

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