Formula for perimeter of a square: P = 4a
Formula for area of a square: A = a²
a is given as:
19
Plug this value for a into the above formulas to solve for perimeter and area.
P = 4a
P = 4(19)
P = 76
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A = a²
A = 19²
A = 361
Answer:
P = 76 units; A = 361 units².
Once cross multiplied you end up with this:
15x+75=20x−30
Next subtract 20x from both sides.
15x+75−20x=20x−30−20x
−5x+75=−30 -----------> Answer
Now subtract 75 from both sides
−5x+75−75=−30−75
−5x=−105
Now divide by -5 on both sides.
-5/-5x = -105/-5
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x = 21 --------------> ANSWER</h3>
The answer is $57.60
(The original price) 45+ 12.60 (28% of 45) = 57.60
