Answer:
4
similar right triangles
Step-by-step explanation:
Answer:
a) 
b) 
Step-by-step explanation:
Polar coordinates are represented as: 
, where 'r' is the length (or magnitude) of the line, and '
' is the angle measured from the positive x-axis.
in our case:
to covert the polar to cartesian:
we can plug in our values:
the Cartesian coordinates are:
(b) to convert (x,y) = (6.06,-3.5)
we'll use the pythagoras theorem to find 'r'
the angle can be found by:
to convert radians to degrees:
writing in polar coordinates:
<h3>
Answer: Choice D. 4x^2 + 20x + 25</h3>
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Explanation:
Perfect square trinomials are in the form (a+b)^2 = a^2+2ab+b^2
So the first and last terms must be perfect squares. The middle term is twice that of the square roots of each first and last term.
Choice D fits the description because 4x^2 = (2x)^2 is the first term, so a = 2x and 25 = 5^2 is the last term meaning b = 5. Note how 2ab = 2*2x*5 = 20x is the middle term.
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(a+b)^2 = a^2+2ab+b^2
(2x+5)^2 = (2x)^2+2*2x*5+5^2
(2x+5)^2 = 4x^2 + 20x + 25
