Answer:
590 would be your answer
Step-by-step explanation:
Ok, to show that she is incorrect we can use any other number in both equations and they will not be equal. the number she used does turn out equal but that does not mean the equations are equal.
for example
2 times 3=6
3 to the power of 2 is 9
that shows the expressions are not equal
You want to find values of v (number of visors sold) and c (number of caps sold) that satisfy the equation
... 3v + 7c = 4480
In intercept form, this equation is
... v/(1493 1/3) + c/640 = 1 . . . . . divide by 4480
Among other things, this tells us one solution is
... (v, c) = (0, 640)
The least common multiple of 3 and 7 is 21, so decreasing the number of caps sold by some multiple of 3 and increasing the number of visors sold by that same multiple of 7 will result in another possible solution.
The largest multiple of 21 that is less than 4480 is 213. Another possible solution is (0 +213·7, 640 -213·3) = (1491, 1)
We can also pick some number in between, say using 100 as the multiple
... (0 +100·7, 640 -100·3) = (700, 340)
In summary, your three solutions could be
... (visors, caps) = (0, 640), (700, 340), (1491, 1)