Answer:
we have (a,b,c)=(4,-2,0) and R=4 (radius)
Step-by-step explanation:
since
x²+y²+z²−8x+4y=−4
we have to complete the squares to finish with a equation of the form
(x-a)²+(y-b)²+(z-c)²=R²
that is the equation of a sphere of radius R and centre in (a,b,c)
thus
x²+y²+z²−8x+4y=−4
x²+y²+z²−8x+4y +4 = 0
x²+y²+z²−8x+4y +4 +16-16 =0
(x²−8x + 16) + (y² + 4y + 4 ) + (z²) -16 = 0
(x-4)² + (y+2)² + z² = 16
(x-4)² + (y-(-2))² + (z-0)² = 4²
thus we have a=4 , b= -2 , c= 0 and R=4
Answer:
hi
Step-by-step explanation:
Hat means y + z = 180.
<span>y is thrice than z means y = 3 * z. </span>
<span>replace y with 3 * z in the equation of y + z = 180 to get 3 * z + z = 180. </span>
<span>combine like terms to get 4 * z = 180. </span>
<span>solve for z to get z = 180 / 4 = 45 degrees. </span>
<span>since y = 3 * z, then y = 3 * 45 = 135 degrees. </span>
y = 135
<span>z = 45 </span>
y + z = 180 becomes 135 + 45 = 180
<span>y = 3 * z = 135 = 3 *45 </span>
<span>solution is confirmed to be good.</span>
