Answer:

Step-by-step explanation:
The given cylindrical equation is

Multiply both sides by r.
.... (1)
The required formulas are

Substitute
in equation (1).


Add 1 on both sides.

![[\because (a-b)^2=a^2-2ab+b^2]](https://tex.z-dn.net/?f=%5B%5Cbecause%20%28a-b%29%5E2%3Da%5E2-2ab%2Bb%5E2%5D)
It is the equation of a circle centered at (0,1) with radius 1.
Therefore, the equation in rectangular coordinates is
.
Answer: $75.99
Steps: 149×0.6= 89.4
Multiply 89.4×0.85= 75.99
Hope this helps ʕ•ᴥ•ʔ
Answer:
The answer is A, (1,2).
Step-by-step explanation:
Hope this helps!
8x-4(x+1) = 0
x =1
y = 1 + 1
y = 2
(x,y) = (1,2)
2 = 1 + 1
8 x 1 - 4 x 2 = 0
Simplify
2 = 2
0 = 0
Solution = (1 , 2)
Answer:
1) {y,x}={-3,-23}
2) {x,y}={7,-9/2}
Step-by-step explanation:
Required:
- Solve systems of equations
1) y - x = 20, 2x - 15y = -1
Equations Simplified or Rearranged :
[1] y - x = 20
[2] -15y + 2x = -1
Graphic Representation of the Equations :
x + y = 20 2x - 15y = -1
Solve by Substitution :
// Solve equation [1] for the variable y
[1] y = x + 20
// Plug this in for variable y in equation [2]
[2] -15•(x +20) + 2x = -1
[2] - 13x = 299
// Solve equation [2] for the variable x
[2] 13x = - 299
[2] x = - 23
// By now we know this much :
y = x+20
x = -23
// Use the x value to solve for y
y = (-23)+20 = -3
Solution :
{y,x} = {-3,-23}
2) 25-x=-4y,3x-2y=30
Equations Simplified or Rearranged :
[1] -x + 4y = -25
[2] 3x - 2y = 30
Graphic Representation of the Equations :
4y - x = -25 -2y + 3x = 30
Solve by Substitution :
// Solve equation [1] for the variable x
[1] x = 4y + 25
// Plug this in for variable x in equation [2]
[2] 3•(4y+25) - 2y = 30
[2] 10y = -45
// Solve equation [2] for the variable y
[2] 10y = - 45
[2] y = - 9/2
// By now we know this much :
x = 4y+25
y = -9/2
// Use the y value to solve for x
x = 4(-9/2)+25 = 7
Solution :
{x,y} = {7,-9/2}