The complete question in the attached figure
we know that
the equation of a sphere is
(x-h)²+(y-k)²+(z-l)²=r²
<span>let's assume that the center of the sphere is at the origin
</span>so
(h,k,l)-------> (0,0,0)
for r=16 m
(x-h)²+(y-k)²+(z-l)²=r²--------> (x)²+(y)²+(z)²=16²
for z=9 m
(x)²+(y)²+(9)²=16²--------> (x)²+(y)²=256-81--------> (x)²+(y)²=175
the radius of the circle is r=√175 m
so the area of the circle A=pi*r²-----> A=pi*175-----> A=549.5 m²
the answer is the area of the circle is 549.5 m²
slope =(y2-y1)/(x2-x1)
m=(-1-5)/(1--1)
m=-6/2
m=-3
y-y1=m(x-x1) point slope form
y-5 = -3 (x--1)
y-5 = -3 (x+1)
distribute
y-5 = -3x -3
add 5 to each side
y = -3x+2
Choice D
It was about 17.4%
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% error=
actual value-estimated value
Then divide that by actual value
8x-9y=19
4x+y=-7
Multiply all terms of the 2nd by (9)===> 36x + 9y= 63
add (36x 9y= 63) to the 1st ===> 44x+0y = -44 ===> x=-1
replace x by this value in any of the equation & you'll get y=-3