The cost has increased by $2.25 which means the cost per kilogram is now 15+2.25 = 17.25 dollars
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As a slight shortcut, we can multiply the old cost (15) by the multiplier 1.15 to get the same result:
1.15*15 = 17.25
This method allows us to chain together many percentage increases, and it also allows us to include percentage decreases as well. Note how 1.15 is basically the result of 100% + 15% = 1.00+0.15 = 1.15
The slope of a linear line (or a linear equation) can be found by simply taking 2 values for x and y and then using the slope formula which is or:
Example:
Let's say you're give this table:
x: 1, 2
y: 1, 2
Following the steps which I gave, you take 1 value for the y (preferably the larger one) which in this cause will be 2 and then another y from the table which would be 1
Do the same for x
Now plug the values taken in the slope formula and you get: