Exercise A: Patterns --Finding Formulas and Missing Values 1.
Andre selts silicon cell phone covers at his stall. His fixed cost is R500 per month and he
pays R25 per cell phone cover. His costs are shown in the table below:
Number of items (n)
144 4
2 3 10
Total cost in Rand (0) 500 525 550 575
875
(a) Find the formula for calculating his total cost. Use C for total cost and n for the
number of cell phone covers.
(b) Hence, calculate the values of the unknown letters. Show all your steps.
0
1
В
A​

be more specific

step-by-step explanation:

-3

step-by-step explanation:

a drawing really does here:

so i draw the horizontal line y=2 and the vertical line x=-2 at this intersection i put b (this is where my right angle is going to be).   so point b is at (-2,2).   point a is 5 units long and is also on y=2 so this point has to be (3,2) or (-7,2) -doesn't matter i will go with (3,2).

now we know c is at (-2,y) we don't know the y yet bet we know that c is on x=-2.

we have the area of the triangle is .5bh=12.5

we know the base length is 5 (ab)

we have the height is (2-y) if you look at your

plug in

.5(5)(2-y)=12.5

solve for y to get the y-coordinate for c

2.5(2-y)=12.5

divide both sides by 2.5 giving:

2-y=5

now subtract 2 on both sides

-y=3

y=-3

step-by-step explanation: