Answer:
y=1/8(-x^2+4x+44
Step-by-step explanation:
In this question the given focus is (2,4) and a directrix of y = 8 and we have to derive the equation of the parabola.
Let (x,y) is a point on the given parabola.Then the distance between the point (x,y) to (2,4) and the distance from (x,y) to diractrix will be same.
Distance between (x,y) and (2,4)
= √(x-2)²+(y-4)²
And the distance between (x,y) and directrix y=8
= (y-8)
Now √(x-2)²+(y-4)² = (y-8)
(x-2)²+(y-4)² = (y-8)²
x²+4-4x+y²+16-8y = y²+64-16y
x²+20+y²-4x-8y = y²-16y+64
x²+20-4x-8y+16y-64=0
x²+8y-4x-44 = 0
8y = -x²+4x+44
The pyramid is shown in the diagram below.
The pyramid is built from four congruent triangles and one square as the base
We have the side of the square, so the area is = 10×10 = 100
We need the height of the triangle to work out its area. We can find out by using the height of the pyramid and half of the length of the side of the square.
Using the Pythagoras rule
Height of triangle =

Area of one triangle = 1/2×10×12=60
Surface area of the pyramid = 100 + (4×60) = 340 square inches
Answer:
See below
Step-by-step explanation:
![9.( {m}^{3} {n}^{5} )^{ \frac{1}{4} } \\ = m^{\frac{3}{4}}n^{\frac{5}{4}}\\ \\ 10. \sqrt[5]{ \sqrt[4]{x} } \\ = \sqrt[5]{ {x}^{ \frac{1}{4} } } \\ = {( {x}^{ \frac{1}{4} } )}^{ \frac{1}{5} } \\ = {x}^{ \frac{1}{4} \times \frac{1}{5} } \\ = {x}^{ \frac{1}{20} } \\ \\ \sqrt[5]{ \sqrt[3]{ {a}^{2} } } \\ = \sqrt[5]{ {a}^{ \frac{2}{3} } } \\ = {( {a}^{ \frac{2}{3} } )}^{ \frac{1}{5} } \\ = {a}^{ \frac{2}{3} \times \frac{1}{5} } \\ = {a}^{ \frac{2}{15} }](https://tex.z-dn.net/?f=9.%28%20%7Bm%7D%5E%7B3%7D%20%20%7Bn%7D%5E%7B5%7D%20%29%5E%7B%20%5Cfrac%7B1%7D%7B4%7D%20%7D%20%20%20%5C%5C%20%20%20%3D%20%20m%5E%7B%5Cfrac%7B3%7D%7B4%7D%7Dn%5E%7B%5Cfrac%7B5%7D%7B4%7D%7D%5C%5C%20%20%5C%5C%2010.%20%5Csqrt%5B5%5D%7B%20%5Csqrt%5B4%5D%7Bx%7D%20%7D%20%20%5C%5C%20%20%3D%20%20%5Csqrt%5B5%5D%7B%20%7Bx%7D%5E%7B%20%5Cfrac%7B1%7D%7B4%7D%20%7D%20%7D%20%20%5C%5C%20%20%3D%20%20%7B%28%20%7Bx%7D%5E%7B%20%5Cfrac%7B1%7D%7B4%7D%20%7D%20%29%7D%5E%7B%20%5Cfrac%7B1%7D%7B5%7D%20%7D%20%20%5C%5C%20%20%20%3D%20%20%7Bx%7D%5E%7B%20%5Cfrac%7B1%7D%7B4%7D%20%20%5Ctimes%20%20%5Cfrac%7B1%7D%7B5%7D%20%7D%20%20%5C%5C%20%20%3D%20%20%7Bx%7D%5E%7B%20%5Cfrac%7B1%7D%7B20%7D%20%7D%20%20%5C%5C%20%20%5C%5C%20%5Csqrt%5B5%5D%7B%20%5Csqrt%5B3%5D%7B%20%7Ba%7D%5E%7B2%7D%20%7D%20%7D%20%20%5C%5C%20%20%3D%20%20%5Csqrt%5B5%5D%7B%20%7Ba%7D%5E%7B%20%5Cfrac%7B2%7D%7B3%7D%20%7D%20%7D%20%20%5C%5C%20%20%3D%20%20%7B%28%20%7Ba%7D%5E%7B%20%5Cfrac%7B2%7D%7B3%7D%20%7D%20%29%7D%5E%7B%20%5Cfrac%7B1%7D%7B5%7D%20%7D%20%20%5C%5C%20%20%20%3D%20%20%7Ba%7D%5E%7B%20%5Cfrac%7B2%7D%7B3%7D%20%20%5Ctimes%20%20%5Cfrac%7B1%7D%7B5%7D%20%7D%20%20%5C%5C%20%20%3D%20%20%7Ba%7D%5E%7B%20%5Cfrac%7B2%7D%7B15%7D%20%7D%20%20)
Answer:
13
Step-by-step explanation:
Answer:
x = 38
Step-by-step explanation:
using the law of logarithms
•
x = n ⇔ x =
, hence
(2x - 12) = 3 ⇒ 2x - 12 =
= 64
add 12 to both sides
2x = 76 ( divide both sides by 2 )
x = 38