You would need to know the cost of the box of 20, then you would divide the total cost by the number of pencils in the box. This would give you the cost of one pencil - which is the unit cost.
Example:
Lets say the box of 20 pencils cost $10.
Divide the total cost by the number of pencils:
10 / 20 = 0.50 - This means each pencil cost 50 cents, so the unit cost would be 50 cents per pencil.
<span>Any ordered pair in a system that makes all the equations true
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Answer:
Step-by-step explanation:
Answer:
see explanation
Step-by-step explanation:
(1)
Given
3(x + 3)² - 1 = - 13 ( add 1 to both sides )
3(x + 3)² = - 12 ( divide both sides by 3 )
(x + 3)² = - 4 ( take the square root of both sides )
x + 3 = ±
= ± 2i ( subtract 3 from both sides )
x = - 3 ± 2i ← complex conjugate roots
(2)
Given
3x² - 12x + 27 = 0 ( subtract 27 from both sides )
3x² - 12x = - 27 ( divide through by 3 )
x² - 4x = - 9
To complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(- 2)x + 4 = - 9 + 4
(x - 2)² = - 5 ( take the square root of both sides )
x - 2 = ±
= ± i
( add 2 to both sides )
x = 2 ± i
← complex conjugate roots
Answer:
3 lines
Step-by-step explanation: