Answer:
(- 5, - 7 )
Step-by-step explanation:
Equate f(x) and g(x), that is
2x + 3 = - 4x - 27 ( add 4x to both sides )
6x + 3 = - 27 ( subtract 3 from both sides )
6x = - 30 ( divide both sides by 6 )
x = - 5
Substitute x = - 5 into either of the 2 functions for y- coordinate
Substituting into f(x)
f(- 5) = 2(- 5) + 3 = - 10 + 3 = - 7
Thus point of intersection = (- 5, - 7 )
Answer: Choice D)
The angle between the two vectors is approximately 71.6 degrees
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Work Shown:
Each time I write the word "dot" I mean "dot product".
|u| = length of vector u
|u| = sqrt(u dot u)
|u| = sqrt(<8,4> dot <8,4>)
|u| = sqrt(8*8 + 4*4)
|u| = sqrt(64 + 16)
|u| = sqrt(80)
|u| = sqrt(16*5)
|u| = sqrt(16)*sqrt(5)
|u| = 4*sqrt(5)
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|v| = length of vector v
|v| = sqrt(v dot v)
|v| = sqrt(<9,-9> dot <9,-9>)
|v| = sqrt(9*9 + (-9)*(-9))
|v| = sqrt(81+81)
|v| = sqrt(2*81)
|v| = sqrt(2)*sqrt(81)
|v| = sqrt(2)*9
|v| = 9*sqrt(2)
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u dot v = <8,4> dot <9,-9>
u dot v = 8*9 + 4*(-9)
u dot v = 72-36
u dot v = 36
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cos(theta) = (u dot v)/(|u|*|v|)
cos(theta) = (36)/(4*sqrt(5)*9*sqrt(2))
cos(theta) = (36)/(36*sqrt(10))
cos(theta) = 1/(sqrt(10))
cos(theta) = sqrt(10)/10
theta = arccos(sqrt(10)/10)
theta = 71.56505
which rounds to 71.6 when rounding to one decimal place (nearest tenth)
That's why the approximate answer is roughly 71.6 degrees
1 2/3 is the answerrrrrrr
As a engineer who was mechanical then electrical most buildings, schematics,etc require some form of calculation for some shapes seeing that those shapes are what make up the world. Say for example you need to make something like a mother board pro house knowing it's shape and angle helps make a more accurate structure during the blue printing and build phase. No one just goes in and wings it you need to determine angles for things you don't know that the point of it.
