Question

1. the amount of fuel in litres, f, that is left in the tank of a certain vehicle can be found using the following formula, where d is the distance in kilometres driven since the tank was full. how far can the vehicle travel on 45 l of fuel?

f = -0.074d + 77.5
method #1: substitute & rearrange\tmethod 2: rearrange & substitute

1. the equivalent temperature to convert from degrees celsius to degrees fahrenheit can be found using the following formula, where f is the temperature in fahrenheit and c is the temperature in degrees celsius. determine the temperature in degrees celsius if the thermostat reads 68°f.

f = 1.8c + 32
method #1: substitute & rearrange\tmethod 2: rearrange & substitute

Explanation:

Problem 1

Step1: Substitute f=45 into formula

$45 = -0.074d + 77.5$

Step2: Isolate the term with d

$-0.074d = 45 - 77.5$
$ -0.074d = -32.5$

Step3: Solve for d

$d = \frac{-32.5}{-0.074}$

Step1: Substitute F=68 into formula

$68 = 1.8C + 32$

Step2: Isolate the term with C

$1.8C = 68 - 32$
$1.8C = 36$

Step3: Solve for C

$C = \frac{36}{1.8}$

Answer:

$\approx 439.19$ kilometres

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Problem 2