Answer:
t=1
Step-by-step explanation:
If we multiply the bottom equation by 2 and move x to the right, it becomes:
4y = 2x-38
Now we can substitute it for the 4y in the top equation:
3x + (2x-38) = -23 => 5x = -23+38 => 5x = 15 => x=3
Then 4y = 2*3-38 => y = -8
So the solution is (3,-8)
Hopefully this helps, I have tried to write out all reasoning
Let Mike sold M cars and Bill sold B cars.
Now both sold 640 cars in total, means M + B = 640,
also Mike sold 3 times as many as Bill, means M = 3*B. So our equations became,
M + B = 640, & M = 3*B, put value of M in terms of B.
3*B + B = 640, 4*B = 640,
B = 640/4, B = 160, as M = 3*B, M = 3*160 = 480.
So Mike sold 480 cars & Bill sold 160 cars.
