She must run about 17.5 miles a day
Answer:
-2.33
Step-by-step explanation:
Let the number be denoted as "x"
-45x + 12 = 117
-45x = 117-12
-45x = 105
x = 105/-45
x= -2.33
Answer:
over the interval [2,3)
for an input value of 1.5, the corresponding output value is -2
Step-by-step explanation:
Distance<-------------300--------------><-------------------x----------------->
⊕---------------------------------⊕--------------------------------------⊕ Express Freight Overtaking point
Speed 55 speed 30
Let x be the distance travelled by Freight until the point of overtaking
Time = Distance/Speed, then:
Time (freight) = Distance (fright)/Speed (freight) And
Time (Express) = Distance (Express)/Speed (Express).
Now plug in the relative number:
Time (freight) = x/30 and Time (express) = (x+300)/55. But note that both times are equal, then:
x/30 = (x+300)/55 OR (x÷30 = (x+300)÷55) [Answer C]
Now let's find the distance x. Cross multiplication;
55x= 30(300+x) →55x = 9,000 + 30x
55x - 30x = 9,000 → 25x = 9,000 and x = 9,000/25 = 360 miles
Time needed for Freight to travel 360 m = 360/30= 12 Hours
Time needed for Express to travel (300+360) m = 660/55= 12 Hours
As you see, it's the same time of 12 hours
Don't forget that Distance = Speed x time or time = Distance/Speed, etc.