I believe it's 15, but correct me if I'm wrong
This is because there is one 10 in 15. This gives you 3 tens and 5 in the ones.
Turn both equations into slope-intercept form [ y = mx + b ].
x + 3y = 3
~Subtract x to both sides
3y = 3 - x
~Divide 3 to everything
y = 1 - x/3
~Reorder
y = -1/3x + 1
4x + 3y = -6
~Subtract 4x to both sides
3y = -6 - 4x
~Divide 3 to everything
y = -2 - 4x/3
~Reorder
y = -4/3x - 2
Graph of the equations will be shown below. Note that the solution of graphing two equations will be where both equations intersect. Both lines intersect at (-3, 2), hence making that the solution.
Best of Luck!
I would say D my dear friend from what i see from the patterns hope it helps :) and sorry if its wrong i tried lol
Answer:
7.5 seconds
Step-by-step explanation:

Thus, the time required for the object to return to its point of departure is 7.5 seconds.