David is driving on the highway. He begins the trip with 14 gallons of gas in his car. The car uses up one gallon of gas every 2
0 miles. Let G represent the number of gallons of gas he has left in his tank, and let D represent the total distance (in miles) he has traveled. Write an equation relating G to D, and then graph your equation.
1 answer:
Answer:
Graph in the image attached.
Step-by-step explanation:
Using the model of a linear equation, we have:
'b' is the y-intercept of the equation, that is, the inicial value of G, when D = 0.
So if David starts the trip with 14 gallons of gas, we have b = 14.
'a' is the slope of the line, that is, an increase of 1 in the value of D causes an increase of 'a' in the value of G.
So if the car uses one gallon every 20 miles, the value of a is -1/20 (an increase of 20 in D causes a decrease of 1 in G).]
So our equation is:
The graph of this equation is in the image attached.
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