You would plot them by month, 170-110= 60 dollar increase. 60 divided by 12 ( for each month) leaves a 5 dollar increase each month. Your coordinates would be 0,110 1,115 2,120 3,125
x would be month
y would be money
The easiest way to find the factors of a pair of numbers, is simply to
write out the factors until you find the ones that they have in common.
So in this case, these factors would be listed as follows:
20: 1,2,4,5,10,20
50: 1,2,5,10,25,50.
From looking at these numbers, we can therefore see that the common factors are: 1,2,5,10
To work out how much Luz earns, you simply have to follow 400/40=10, so
she earns $10/hour. We can therefore establish that if she works for 6
hours, she'll earn $60.