After 12 months, Quynh will have saved $800
Simply follow the pattern shown on the graph.
Month 1: 250
Month 2: 300
Month 3: 350
Month 4: 400
Month 5: 450
Month 6: 500
Month 7: 550
Month 8: 600
Month 9: 650
Month 10: 700
Month 11: 750
Month 12: 800
Assuming that the cost per minute is the same for both months and the plan fee is the same, you can use y=mx+b for this
y is the cost of the phone plan, x is the cost per minute and b is the start cost.
so 19.41=25x+b for the first month
and 45.65=380x+b for the second month
solve both for b you get:
19.41-25x=b and 45.65-380x=b. from this we get
19.41-25x=45.65-380x
solve for x
328x=26.24 and x=0.08
this means the cost per minute is 0.08c/min (answer A)
rewrite the equation to calculate b, and where this time, the x is the number of minutes talked.
y=0.08x+b and plug in one of the two months
45.65=0.08 * 380 + b
Solve for b and b is 15.25
so the final equation is
y=0.08x+15.25 (answer B)
Answer:
<em>The distance of the line is 10.82</em>
Step-by-step explanation:
Distance Between two Points in the Plane
Given two points A(x1,y1) and B(x2,y2), the distance between them is:
The graph clearly shows the points (-5,4) (4,-2), thus the distance is:
The distance of the line is 10.82
