Hi, I am new here, and could really use some help, a word problem involving algebra

[tryingtolearn]

A certain mountain has an elevation of 19,210 feet. In 1907, the glacier on this peak covered 6 acres. By 2000, this glacier had melted to only 1 acre.

a.) Assume that this glacier melted at a constant rate each year. Find this yearly rate.

b.) Use your answer from part a to write a linear equation that gives the acreage A of this glacier t years past 1907.

The fomula to solve this would help me out immensely, thank you so much!

 

[mmm4444bot]

Hi. This is a tutoring site. We can help you, once we know where you're stuck. (We do not teach classroom material here.) Also, let us know if there are any words or phrases in the given information that you do not understand.

What have you learned about the equations of lines so far? Do you know how to calculate slope?

Part (a) says, "Assume that this glacier melted at a constant rate each year. Find this yearly rate."

The word rate means slope, here. The statement about "constant rate" tell us that the graph is a line. They want you to use the equation of a line to model the glacier shrinkage in terms of what year it is.

If the equation y = mx + b looks familiar to you, then symbol y stands for the acreage and symbol x stands for the year.

Begin by associating the given values for the two (x,y) points on the line -- or, I could also say the (year,acre) points on the line. Make sure you match the correct number of acres with the proper year.

Next, substitute these values into the Slope Formula.

Cheers :cool:

PS: If you ever read something that you do not understand, you're certainly free to come back and ask a specific question about it.

 

[HallsofIvy]

A certain mountain has an elevation of 19,210 feet. In 1907, the glacier on this peak covered 6 acres. By 2000, this glacier had melted to only 1 acre.

a.) Assume that this glacier melted at a constant rate each year. Find this yearly rate.

It originally covered 6 acres, but went down to 1. How many acres did it lose? It lost that in 2000- 1907= 93 years. How many "acres per year" is that?

b.) Use your answer from part a to write a linear equation that gives the acreage A of this glacier t years past 1907.

The fomula to solve this would help me out immensely, thank you so much!

Yes, I sure being given the answer would help you get a good grade for this but it wouldn't help you learn. This problem asks you to determine what the formula is- that's what mathematics is, determining what formulas give you the answer, not just putting numbers into formulas someone else gave you. You know that the initial value in 1907, and, from (a), you know what the change is every year. You ought to be able to write down the "formula" immediately from that. For example, if something has intial value 300 and loses 5 every year, then after 1 year it has 300- 5= 195, because you have subtracted 5. After 2 years, 195- 5= 190 which is the same as (300- 5)- 5= 300- 2(5)- you have subtracted 5 for each year. After 3 years, 190- = 185 which is the same as ((300- 5)- 5))- 5= 300- 3(5)- you have subtracted 5 for each of the three years. After "t" years, you will have subtracted 5 t times: 300- 5t. You do the same with the information you are given.