The equation of a sphere is:
(x – h)^2 + (y – k)^2 + (z – l)^2 = r^2
where h, k and l are the coordinates of the center of the
sphere
Using the midpoint formula, the coordinate of the center
is:
h = (-4 + 6) / 2 = 1
k = (7 + -5) / 2 = 1
l = (6 + 7) / 2 = 6.5
so the equation becomes:
(x – 1)^2 + (y – 1)^2 + (z - 6.5)^2 = r^2
we plug in any point, in this case point P to solve for r:
(-4 -1)^2 + (7 – 1)^2 + (6 - 6.5)^2 = r^2
r^2 = 61.25
So the full equation is:
<span>(x – 1)^2 + (y – 1)^2 + (z - 6.5)^2 = 61.25</span>
The slope of the parallel line is -6/7
the slope of the perpendicular line is 7/6
the slope of the line = -6/7
the gradient of two parallel lines are equal
the product of the gradient of two perpendicular lines is -1
: the gradient m1*m2 = -1
m2= -1(-6/7)
m2= 7/6
Step 1: Find the slope
(y-y)/(x-x) = (8-8)/(9+4) = 0
Step 2: Substitute into the slope intercept equation
y - y = m(x - x)
y - 8 = 0(x - 9)
If the problem just wants plain, slope intercept form, then this is your answer.
If not, y = 8
