Answer:
7.49
Step-by-step explanation:
Well first you have to find how much the bike lock cost.
8.75 x 0.2
1.75 = how much 20% of 8.75 is
8.75-1.75
7 = the cost of the bike lock with the 20% markdown
Now you have to find the sales tax.
7 x 0.07
0.49
7 + 0.49
7.49 = total cost with all the stuff
Hopefully this was helpful. There is a shorter method too tho.
Formula for slope: 
y₂: 6
y₁: 8
x₂: 1
x₁: -2
Plug them into the slope equation:
--> 
---> 
The slope is .
Answer:
we need the graph to answer the question
Step-by-step explanation:
we wont know much he makes each week without the graph
Elga’s age is 40 and Alvin’s age is 54
Problem 7: Correct
Problem 8: Correct
Problem 9: Correct
The steps are below if you are curious
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Problem 7
S = 180*(n-2)
2340 = 180*(n-2)
2340/180 = n-2
13 = n-2
n-2 = 13
n = 13+2
n = 15
I'm using n in place of lowercase s, but the idea is the same. If anything, it is better to use n for the number of sides since S already stands for the sum of the interior angles. I'm not sure why your teacher decided to swap things like that.
===========================================================================================
Problem 8
First find y
y+116 = 180
y+116-116 = 180-116
y = 64
which is then used to find x. The quadrilateral angles add up to 180*(n-2) = 180*(4-2) = 360 degrees
Add up the 4 angles, set the sum equal to 360, solve for x
x+y+125+72 = 360
x+64+125+72 = 360 ... substitution (plug in y = 64)
x+261 = 360
x+261-261 = 360-261
x = 99
===========================================================================================
Problem 9
With any polygon, the sum of the exterior angles is always 360 degrees
The first two exterior angles add to 264. The missing exterior angle is x
x+264 = 360
x+264-264 = 360-264
x = 96
