Answer:
y = -x - 7
Step-by-step explanation:
As we move from the point (3, -4) to the point (5, -6), x increases by 2 and y decreases by 2. Thus, the slope of this line is m = rise / run = -2/2, or -1.
Starting with the general slope-intercept form of the equation of a straight line, we get y = mx + b => y = -1x + b.
Subbing -4 for y and 3 for x, we get
-4 = -1(3) + b, which yields b = -1
Thus, the desired equation is
y = -x - 1
where x represents the car's speed in miles per hour. Determine the fuel economy
when the car is traveling 40, 50, and 60 miles per hour.
Answer:
a) 29.50 miles per gallon b) 29.87 miles per gallon c) 28.19 miles per gallon
Step-by-step explanation:
A specific car fuel economy (miles/gallon) = f(x) = 0.00000056x^4 - 0.000018x^3 - 0.016x^2 + 1.38x - 0.38
where x represents the car speed in miles per hour.
when x = 40 miles per hour
A specific car fuel economy (miles/gallon) = f(x) = 0.00000056(40)^4 - 0.000018(40)^3 - 0.016(40)^2 + 1.38(40) - 0.38 = 1.4336 - 1.152 - 25.6 + 55.2 - 0.38 = 29.50 miles per gallon
Similarly,
when x = 50
A specific car fuel economy (miles/gallon) = f(x) = 0.00000056(50)^4 - 0.000018(50)^3 - 0.016(50)^2 + 1.38(50) - 0.38 = 3.5 - 2.25 - 40 + 69 - 0.38 = 29.87 miles per gallon
Similarly,
when x = 60
A specific car fuel economy (miles/gallon) = f(x) = 0.00000056(60)^4 - 0.000018(60)^3 - 0.016(60)^2 + 1.38(60) - 0.38 = 7.26 - 3.89 - 57.6 + 82.8 - 0.38 = 28.19 miles per gallon
Answer:
118 5/12
Step-by-step explanation:
9 2/3 × 12 1/4 = 2 + 9·3/3 ×1 + 12·4/4 = 29/3 × 49/4 = 29·49/3·4 = 1421/12 5 + 118·12/12= 118 5/12