Answer:
<u>BC = 3.1666</u>
Step-by-step explanation:
To solve this you need to know that cosine∅ = adjacent/hypotenuse. We already know that hypotenuse = 5 and that ∅ = 70*. By substituting these in you will get cosine 70* = adjacent/5. Evaluate cosine 70* on the calculator and get 0.633... Multiply both sides by 5 and get adjacent is about equal to 3.1666. Because BC is the adjacent side of the triangle, this is the length of BC.
Multiply the first equation by 2 to then use elimination by adding the 2 equations.
So, 14x-2y=14
+. x+2y=6
Equals 15x=20 so x=20/15=4/3
Plug in to first equation to get y
7(4/3)-y=7
28/3-y=7
28/3-y=21/3
So y=7/3
Plug both x and y into second equation to check
4/3+2(7/3)=
4/3+14/3=18/3=6 it works
So x=4/3, y=7/3
Hope this helps! Have a blessed day!
X = -3.
The distance from p(-9, 0, 0) is
d = sqrt((x+9)^2 + y^2 + z^2)
The distance from q(3,0,0) is
d = sqrt((x-3)^2 + y^2 + z^2)
Let's set them equal to each other.
sqrt((x+9)^2 + y^2 + z^2) = sqrt((x-3)^2 + y^2 + z^2)
Square both sides, then simplify
(x+9)^2 + y^2 + z^2 = (x-3)^2 + y^2 + z^2
x^2 + 18x + 81 + y^2 + z^2 = x^2 - 6x + 9 + y^2 + z^2
18x + 81 = - 6x + 9
24x + 81 = 9
24x = -72
x = -3
So the desired equation is x = -3 which defines a plane.