Answer:
66.42°
Step-by-step explanation:
<u>Given:</u>
A(5, 3t+2, 2)
B(1, 3t, 2)
C(1, 4t, 3)
BA • BC = 4
Step 1: Find t.
First we have to find vectors BA and BC. We do that by subtracting the coordinates of the initial point from the coordinates of the terminal point.
In vector BA B is the initial point and A is the terminal point.
BA = OA - OB = (5-1, 3t+2-3t, 2-2) = (4, 2, 0)
BC = OC - OB = (1-1, 4t-3t, 3-2) = (0, t, 1)
Now we can find t because we know that BA • BC = 4
BA • BC = 4
To find dot product we calculate the sum of the produts of the corresponding components.
BA • BC = (4)(0) + (2)(t) + (0)(1)
4 = (4)(0) + (2)(t) + (0)(1)
4 = 0 + 2t + 0
4 = 2t
2 = t
t = 2
Now we know that:
BA = (4, 2, 0)
BC = (0, 2, 1)
Step 2: Find the angle ∠ABC.
Dot product: a • b = |a| |b| cos(angle)
BA • BC = 4
|BA| |BC| cos(angle) = 4
To get magnitudes we square each compoment of the vector and sum them together. Then square root.







Rounded to two decimal places:

Answer:
First choice.
Step-by-step explanation:
You could plug in the choices to see which would make all the 3 equations true.
Let's start with (x=2,y=-6,z=1):
2x+y-z=-3
2(2)+-6-1=-3
4-6-1=-3
-2-1=-3
-3=-3 is true so the first choice satisfies the first equation.
5x-2y+2z=24
5(2)-2(-6)+2(1)=24
10+12+2=24
24=24 is true so the first choice satisfies the second equation.
3x-z=5
3(2)-1=5
6-1=5
5=5 is true so the first choice satisfies the third equation.
We don't have to go any further since we found the solution.
---------Another way.
Multiply the first equation by 2 and add equation 1 and equation 2 together.
2(2x+y-z=-3)
4x+2y-2z=-6 is the first equation multiplied by 2.
5x-2y+2z=24
----------------------Add the equations together:
9x+0+0=18
9x=18
Divide both sides by 9:
x=18/9
x=2
Using the third equation along with x=2 we can find z.
3x-z=5 with x=2:
3(2)-z=5
6-z=5
Add z on both sides:
6=5+z
Subtract 5 on both sides:
1=z
Now using the first equation along with 2x+y-z=-3 with x=2 and z=1:
2(2)+y-1=-3
4+y-1=-3
3+y=-3
Subtract 3 on both sides:
y=-6
So the solution is (x=2,y=-6,z=1).
What you would do is multiply for this problem.
you turn 35% into a decimal so the problem would look like
0.35 x 120 that should equal 42
hope that helps
Answer:
75%
Step-by-step explanation:
You need to find the total number of votes first. Just add 13 and 39 which would equal 52.
Then divide the number of people in favour by the total number of voters and multiply by a 100 to find the percentage.
39 + 13 = 52
39/52 = 0.75
0.75 x 100 = 75.0
75%
Answer:
2 dollars I guess l d k
Step-by-step explanation:
pay subcription to get good answer k :)