You need to isolate the variables. For the first equation add x to both sides, which leaves you with y.
For the second equation, divide each side by 2 leaving you with
x= 6+y. Subtract y from each side. Subtract x from both sides. Now you have y= x + 6.
Now graph those equations.
For this case we have the following expression:

Rewriting the expression we have:
We apply distributive property to the terms of parentheses:

Answer:

So what you should do is
15% off, then add tax or
2075 times 0.85 times 1.185=2090.04 about
you can't just add and subtract percents because they are percents of different things
what he did was
he found 15% of 2075 and 18.5% of 2075 then found the difference and added to 2075 to find his total
what he should have done is
found the discounted price (15% off) then found the tax on that
first way
2075 times 0.15=311.25
2075-311.25=1763.75
1763.75 times 0.185=326.29375
1763.75-326.29375=2090.04
2nd way (easy, if you understand commutative property and stuff)
100-15=85
1+0.185=1.185
2075*0.85*1.185=2090.04
answer should be $2090.04
Almost all correct except two. Please check corrected image.