5 Select the correct answer Which system of equations is represented by this graph?

Find a cartesian equation for the curve. r = 9 sin(θ)

Paul [167]

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

6 0

3 years ago

Transform the equation formulated into standard form ax²+bx+c=0

nekit [7.7K]

Answer:

ax^2 + bx + c = 0

Here is a specific example:

5x^2 - 3x + 2 = 0

In other words:

You have zero on the right.

On the left, you have the powers of “x” in descending order.

8 0

2 years ago

What is the unit rate of 3.5 miles in 1.25 hours

snow_lady [41]

3.5 miles / 1.25 hours = 2.8 mph

3 0

3 years ago

Geometry question. please help

Vinvika [58]

Answer:

The length of PQ is 18 feet.

The length of PR is 18 feet.

The length of QR is 24 feet.

Step-by-step explanation:

A way to set an equation up for this problem is:

$\frac{4}{3}x+x+x=60$

where x is the three lengths of the isosceles triangle, but the base QR is 4/3 the length of the other two congruent sides, length PQ and PR. The 60 represents the total length of the perimeter.

Then, solve for x from the equation, and you’ll get x=18. But your not done yet. Since the variable x in the equation stands for the sides of the isosceles triangle, so plug 18 into the equation and it should look like this:

$\frac{4}{3}(18)+18+18=60$

Don’t solve the whole equation, just solve the $\frac{4}{3}(18)$ part of the equation, which is equal to 24. So the final equation is this:

$24+18+18=60$

Conclusion: 24 is the length of QR, and 18 is the length of PQ and PR. And they all equal 60, which is the perimeter. This is very true because the length of PQ and PR are the same (length 18), since it’s an isosceles triangle, and the length of QR is 4/3 the length of PQ and PR (4/3 of 18= 24).

Sorry for the long explanation.

But hope this helps and answers your question :)

8 0

3 years ago

- 7(2-1) = 28 The solution is?

Aneli [31]

Answer:

Is there a x somewhere or is that litteraly how the equation is?

If so, -7 multiplied by 2 is -14,

-1 times -7 is 7,

add it together and you get

-7=28,

you could add 7 to both sides or subtract 28 from both sides and you'll get either 0=35 or -35=0

which would make the solution false since both sides are not the same

6 0

3 years ago