Answer:
t = 11 min
and
t = 18 min
Step-by-step explanation:
When we have unidimensional motion, the sign of the velocity defines the direction.
So we could say that a positive velocity like:
v = 4ft/min
Means that you are moving to the right with a speed of 4 feet per minute.
And a negative velocity like:
v = -3 ft/min
means that you are moving to the left with a speed of 3 feet per minute.
Then the bug changes direction when the velocity changes of sign.
In the graph, we can see that the velocity changes of sing in two points, these points are:
t = 11 min
and
t = 18 min
Start by writing out the information you know mathematically (I used S for cost of senior ticket, and C for cost of child ticket. You could use X and Y, or any other combination of letters as variables)
3s + 1c=38
3s + 2c=52
Now, you'll want to eliminate one of the variables by subtracting it out. Remember - Same sign, subtract (and therefore different sign, add).
In this case, 3s exists in the first and second equation, so it's very easy to get rid of. They're both positive, so they have the same sign (+). Same sign, subtract.
3s + 1c=38
-(3s + 2c=52)
__________
0 -1c= -14
-c=-14
C=14
Now, plug c=14 into either of the original equations.
3s + C= 38
3s + 14=38
3s=24
S=8.
So, a child ticket costs $14 and a senior ticket costs $8.
Just ADD 1 +3 then subtract it from 1.4 inch
