Please: Use "^" to denote exponentiation: <span>2x^2 + 8x - 12 = 0
Reduce this by div. every term by 2: </span><span>x^2 + 4x - 6 = 0
Here a=1, b=4 and c = -6. Square half of b, obtaining (4/2)^2 = 4, and add, and then subtract, this 4 to x^2 + 4x - 6:
</span> x^2 + 4x +4 - 4 - 6 = 0. Rewrite the square as (x+2)^2, obtaining new equation
(x+2)^2 = 10. Take the sqrt of both sides: x+2 = plus or minus sqrt(10).
Finally, solve for x: x = -2 plus or minus sqrt(10).
Here is your function graphed
TW x WU = CW x VW
Fill in the known values:
WU = TU - TW = 21.2 - 14.6 = 6.6
14.6 x 6.6 = 6 x VW
Simplify:
96.36 = 6VW
Divide both sides by 6:
VW = 96.36 / 6
VW = 16.06
Round to one decimal place:
VW = 16.1
The answer is D>
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Actually Welcome to the Concept of the Surface Areas and Volumes.
Since, Volume of cone = 1/3 π r^2 h,
here, r = 10 Inches and h= 12 inches, also π =3.14
so, VOC = 1/3 π (10)^2 × (20)
VOC = 1/3(3.14)(100)(20)= 2093.33 inch^3
=> so the volume of the cone is 2093.33 cubic inches.