just make a table with two columns
Each column will have a row for the year # and its associated sales
Solve using table of values
The Winter Sports Shoppe has seen a steady increase in the sales of snowboards over the last three years . They sold 120 snowboards the first year, 280 the second year, and 440 this year. If the pattern continues, how many snowboards might they sell in the sixth year ?
* I know the answer just not sure how to set up the table*
3 answers
Mark years with x and sold snowboards with y.
x1 = 1 , y1 = 120
x2 = 2 , y2 = 280
x3 = 3 , y = 440
y2 - y1 = 280 - 120 = 160
y3 - y2 = 440 - 280 = 160
Difference is constant.
This mean, equation is linear , y = m x + c
m is the slope of the line.
m = ( y2 - y1 ) / ( x2 -x1 )
In this case:
m = ( 280 - 120 ) / ( 2 -1 )
m = 160 / 1 = 160
Replace this value in equation:
y = m x + c
y = 160 x + c
Put x = 1 , y = 120 in equation y = 160 x + c
120 = 160 ∙ 1 + c
120 = 160 + c
120 - 160 = c
c = - 40
Your function is:
y = 160 x - 40
In the sixth year x = 6
y = 160 x - 40
y = 160 ∙ 6 - 40
y = 960 - 40 = 920
x1 = 1 , y1 = 120
x2 = 2 , y2 = 280
x3 = 3 , y = 440
y2 - y1 = 280 - 120 = 160
y3 - y2 = 440 - 280 = 160
Difference is constant.
This mean, equation is linear , y = m x + c
m is the slope of the line.
m = ( y2 - y1 ) / ( x2 -x1 )
In this case:
m = ( 280 - 120 ) / ( 2 -1 )
m = 160 / 1 = 160
Replace this value in equation:
y = m x + c
y = 160 x + c
Put x = 1 , y = 120 in equation y = 160 x + c
120 = 160 ∙ 1 + c
120 = 160 + c
120 - 160 = c
c = - 40
Your function is:
y = 160 x - 40
In the sixth year x = 6
y = 160 x - 40
y = 160 ∙ 6 - 40
y = 960 - 40 = 920
Of course, you can also create a table.
The difference is a constant = 160 and you just put in the table:
year is the previous year + 1
sales = sales of in previes year + 160
The table looks like this.
1 | 120
2 | 280
3 | 440
4 | 600
5 | 760
6 | 920
The difference is a constant = 160 and you just put in the table:
year is the previous year + 1
sales = sales of in previes year + 160
The table looks like this.
1 | 120
2 | 280
3 | 440
4 | 600
5 | 760
6 | 920