Markup means they sell it for that percentage more than they bought it for. First let's calculate how much they will mark it up for:

Convert 87% into a decimal(87/100):

Multiply:

This is how much they'll mark it up, now let's add it to how much they bought it for to find out the selling price:
Add 26 and 73 = 99 then divide 99 by 6 = 16.5 which is 17 vases
I find it easiest to use slope-intercept form, or y=mx+b, to do this.
First, find the slope. 6/3 = 2/1 = 2. m = 2.
Next, find the y-intercept. In this case they gave it to you directly. b = -3.
So, the equation would be y = 2x - 3.
Answer:
7
Step-by-step explanation:
12-(-3)-2(4)
12-(-3)-8
15-8=7
(-4) is the same as x, so looking the conditions that are the results for the function, you realize:
-2 is the result of the function to the values of X that are under -3: the result will be -2 if x < -3
x < -3 ; x = -4 ; -4 < -3 (it's true), in other words, -4 is less than -3, so f(-4) = -2