He was wrong, you cannot make 10 coins by adding 32 coins to 28 coins. If you want to obtain 10 coins from 32 coins and 28 coins, you can subtract 28 coins from 32 coins.
This can be illustrated as follows:
32-28=10
The cost of my me knife is $5.52
So all your doing is plotting the points, for example find 0 then count forward twice- u will plot and label it their. Its the same process for each number. (ps if its negative go backwards)
1,710/3 = 570 <== this is just simple division...nothing a calculator can't do.
What you want to do for each of those is follow the formula, y-y[1]=m(x-x[1]). When I say y[1] and x[1], I mean the x and y values given. So the first one would be y-4=-3(x-(-1)). Then you solve for y by distributing the -3 to x and +1 (+1 because two negatives make a positive), making the equation
y-4=-3x-3. Then you subtract the 4. Answer #1. y=-3x-7.
#2.
y-1=1(x-4)
y-1=x-4
y=x-5
#3.
y-2=2(x-(-1))
y-2=2x+2
y=2x+4
Hope this helped you!