<h3>
Answer: Choice A. Graph (1)</h3>
Reasoning:
If it is at all possible to draw a single vertical line through more than one point on the curve, then the graph is not a function. With graphs (2), (3) and (4), we can draw a vertical line through more than one point on those curves, so they aren't functions. Graph (1) is the only thing left. This graph is a function because it is not possible to draw a single vertical line through more than one point. It passes the vertical line test. Any input (x) leads to exactly one and only one y output.
Nice work on getting the correct answer when you chose "graph (1)".
∠ M ≅ ∠ R: true
<span>VL ≅ LT: true
</span><span>Δ MLV can be rotated about point L to map it to Δ RLT. : false
</span><span>A series of rigid transformations of Δ MLV maps it to Δ RLT. : true </span>
C) (0.85 + x/100)(250+145) does not give the correct answer.
Explanation
A) works; adding the two costs together is 250+145=395. We multiply this by 0.85 because 100%-15%=85%=0.85. We also have x% tax, which is represented by x/100, added to 100% of the value, or 1.00. Altogether this gives us
395(0.85)(1+x/100) = 395(0.85 + (0.85x/100)) = 395(0.85) + 395(0.85x/100)
= 395(0.85) + 395(0.0085x)
B) works; we have 250+145 for the original price; we have 85% = 0.85 of the value; we also have 100% + x%, which is (100+x)/100.
C) does not work; (0.85+x/100)(395) does not take into consideration that you are finding the tax after taking the 85%. This will simplify out to
0.85*395 + (x/100)(395) = 335.75 + 395x/100 = 335.75 + 3.95x, which is too much.
D) works; simplifying the expression from A, we have 395(0.85) + 395(0.0085x) = 335.75 + 3.3575x.
The answer I think is 14 +x3