for any fraction a/b, the decimal format of it is just a ÷ b.
A)
is the number rational?
well, a rational number is one we can write as a ration or fraction, well clearly is a fraction so it is rational.
B)
can it be written as a repeating/recurring decimal? well, 9/20 is 0.45, so -9/20 is -0.45, no repeating decimal like 0.454545......... , just a plain vanilla -0.45, so nope.
C)
is it less than -0.4?
well, let's recall that for the negative side on the number line, the closer to 0, the larger the number, so then -1,000,000 is much smaller than -1, because -1 is closer to 0.
who is closer -0.4 or -0.45?
|--------------------- -0.45 -------- -0.40 ------------------- 0 --------------- 1 -------------------|
so, -0.45 is farther from 0, and therefore is smaller than -0.4, so yes.
For this case we have the following equation:
r = 9 sin (θ)
In addition, we have the following change of variables:
y = r * sine (θ)
Rewriting the equation we have:
r = 9 sin (θ)
r = 9 (y / r)
r ^ 2 = 9y
On the other hand:
r ^ 2 = x ^ 2 + y ^ 2
Substituting values:
x ^ 2 + y ^ 2 = 9y
Rewriting:
x ^ 2 + y ^ 2 - 9y = 0
Completing squares:
x ^ 2 + y ^ 2 - 9y + (-9/2) ^ 2 = (-9/2) ^ 2
Rewriting:
x ^ 2 + 1/4 (2y-9) ^ 2 = 81/4
4x ^ 2 + (2y-9) ^ 2 = 81
Answer:
The Cartesian equation is:
4x ^ 2 + (2y-9) ^ 2 = 81
Answer:
uhhh you said 10 points and there are 5 on the screen.
You have to add 4 and 9 then drop your variable
