Answer:
3. about 7.48 hours
4. about 1.8892 hours
Step-by-step explanation:
Both of these questions make use of the relation ...
time = distance / speed
3. time = (965 mi)/(129 mi/h) ≈ 7.48062 h ≈ 7.48 h
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4. time = (612.1 mi)/(324 mi/h) ≈ 1.889198 h ≈ 1.8892 h
(We have rounded the time to sufficient precision so that the distance at the given speed rounds to the number given.)
Let x represent the number of liters of 50% acid Theresa puts into the mix. The the number of liters of 30% acid will be (420-x). The total amount of acid in the final solution will be ...
0.50x + 0.30(420-x) = 0.45(420)
0.20x + 126 = 189 . . . . . . . . . . . . . . . simplify
0.20x = 63 . . . . . . . . . . . . . . . . . . . . . subtract 126
x = 63/0.20 = 315 . . . . . . . . . . . . . . . liters of 50% solution
(420-x) = 420-315 = 105 . . . . . . . . . liters of 30% solution
Theresa should mix ...
105 liters of 30% solution
315 liters of 50% solution
9514 1404 393
Answer:
x-intercept: 7/6
Step-by-step explanation:
The x-intercept is found by solving for x when y=0.
0 = 6x -7
7 = 6x . . . . . add 7 to both sides of the equation
7/6 = x . . . . divide both sides by 6
The x-intercept is 7/6 = 1 1/6 ≈ 1.167.
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The y-intercept is the constant in the given equation: -7. The slope of 6 tells you the line rises 6 units for 1 unit to the right. So, the point (1, -1) is another point on the graph. The line through those two points, (0, -7) and (1, -1), will intersect the x-axis at x=7/6.
