9514 1404 393
Answer:
cone: 138.16 in²
pyramid: 352 m²
Step-by-step explanation:
Use the appropriate formula from your list of area and volume formulas.
<u>Area of a Cone</u>
A = πr(r +h) . . . . . where r is the radius and h is the slant height
The radius is half the diameter, so is 4 inches.
A = π(4 in)(4 in + 7 in) = 44π in² ≈ 138.16 in²
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<u>Lateral Area of a Square Pyramid</u>
A = 2sh . . . . . where s is the side length of the base and h is the slant height
A = 2(8 m)(22 m) = 352 m²
This is the quadratic equation
x = -b +/- (sq root)(b^2 - 4(a)(c) all over 2a
If inside the square root the value is <0. You can't get an answer.
Now figure the rest out
6% increase
To calculate the percentage increase:
First: work out the difference (increase) between the two numbers you are comparing.
Increase = New Number - Original Number
Then: divide the increase by the original number and multiply the answer by 100.
% increase = Increase ÷ Original Number × 100.
If your answer is a negative number, then this is a percentage decrease.
We know that the points at which the parabola intersects the x axis are
(-5,0) and (1,0)
So the extent between these two points would be the base of the triangle
lets find the length of the base using the distance formula
![\sqrt{[(-5-1)^{2}+(0-0)^{2} ]}](https://tex.z-dn.net/?f=%20%5Csqrt%7B%5B%28-5-1%29%5E%7B2%7D%2B%280-0%29%5E%7B2%7D%20%5D%7D%20%20)
the base b=6
We will get the height of the triangle when we put x=0 in the equation
y=a(0+5)(0-1)
y=-5a
so height = -5a (we take +5a since it is the height)
We know that the area of the triangle =
× 6 × (5a) = 12
15a=12
a= 