Skip to main content
Ch. 3 - Polynomial and Rational Functions
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063당신이 사용하는 게 아니라요?교과서 변경
4장, 문제 23

Write each formula as an English phrase using the word varies or proportional. r = d/t, where r is the speed when traveling d miles in t hours.

검증된 단계별 안내
1
Identify the variables in the formula \(r = \frac{d}{t}\), where \(r\) is the speed, \(d\) is the distance traveled, and \(t\) is the time taken.
Recognize that speed \(r\) depends on both distance \(d\) and time \(t\); specifically, speed increases as distance increases if time is constant, and speed decreases as time increases if distance is constant.
Express the relationship between speed and distance: speed \(r\) varies directly (or is directly proportional) to the distance \(d\) when time \(t\) is held constant.
Express the relationship between speed and time: speed \(r\) varies inversely (or is inversely proportional) to the time \(t\) when distance \(d\) is held constant.
Combine these ideas into a phrase: speed \(r\) varies directly with distance \(d\) and inversely with time \(t\).

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
1m
도움이 되었나요?

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Direct Variation

Direct variation describes a relationship where one quantity changes proportionally with another. If y varies directly as x, then y = kx for some constant k. In the formula r = d/t, speed varies directly with distance when time is constant.
추천 영상:
02:44
Maximum Turning Points of a Polynomial Function

Inverse Variation

Inverse variation occurs when one quantity increases as another decreases, expressed as y = k/x. In the formula r = d/t, speed varies inversely with time when distance is constant, meaning as time increases, speed decreases.
추천 영상:
4:30
Graphing Logarithmic Functions

Translating Formulas into English Phrases

Translating mathematical formulas into English involves expressing relationships using words like 'varies directly' or 'varies inversely.' For r = d/t, this means stating how speed depends on distance and time using proportional language.
추천 영상:
06:36
Solving Quadratic Equations Using The Quadratic Formula