Question

the set of data represents the international air mail rates. what equation would best represent the data if the first column is x and y is the cost in dollars for the weight in that row?
weight not over \trate
0 \t0.5 oz \t$0.60
1 \t1.0 \t1.00
2 \t1.5 \t1.40
3 \t2.0 \t1.80
4 \t2.5 \t2.20
5 \t3.0 \t2.60
6 \t3.5 \t3.00
7 \t4.0 \t3.40
8 \t4.5 \t3.80
9 \t5.0 \t4.20
\\( y = 3.40x + 2.20 \\)
\\( y = 2.20x + 3.40 \\)
\\( y = 0.40x + 0.60 \\)
\\( y = 1.00x + 2.20 \\)

Explanation:

Step1: Identify slope pattern

Observe rate change per weight: $\frac{1.00-0.60}{1-0} = 0.40$

Step2: Verify y-intercept

At $x=0$, $y=0.60$, so $b=0.60$

Step3: Match to linear form

Linear equation: $y=mx+b=0.40x+0.60$

Step4: Confirm with other points

For $x=2$: $y=0.40(2)+0.60=1.40$, matches table data.

Answer:

y = 0.40x + 0.60