Answer:
a
Step-by-step explanation:
y=6x²+12x+2
y=4x²+16x+16
6x²+12x+2=4x²+16x+16
6x²-4x²+12x-16x+2-16=0
2x²-4x-14=0
x²-2x-7=0
x²-2x+1-1-7=0
(x-1)²=8
x-1=±√8=±2√2
x=1±2√2
x≈1±2.83
x≈3.83,-1.83
x=2√2 -1≈1.828≈1.83
Since the price of the coffee itself is $1.25, the gradient of the function will be 1.25 and will give a straight line. However, since the first cup of coffee costs $3, when extrapolated to x = 0, the price is 3 - 1.25 = $1.75 which indicates the cost of using the cup. Therefore this is the y-intercept. This can be expressed as a linear function of y = mx + c where y is the price, m is the gradient, x is the number of times the cup has been filled with coffee, and c is the price of using the cup, giving:
y = 1.25x + 1.75
Answer:
if the width is W and the length is 4 more of twice the width therefore the length is 2W+4
area = length × width
= 2W+4×W
=2W+4
The roof is made up of 2 similar pieces of 2 rectangle shapes.
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Area of a rectangle = Length x Width
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Area of a rectangle = 50 x 14 = 700 ft²
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Area of 2 rectangle pieces:
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Area of 2 rectangle pieces = 700 x 2 = 1400 ft²
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Find the cost:
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1ft² = $2.75
1400 ft² = 2.75 x 1400
1400 ft² = $3850
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Answer: It will cost $3850 to have the roof replaced. (Answer A)
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