Which set of polar coordinates describes the same location as the rectangular coordinates (1,-1) a. (-1, 135 degrees) b. (sqrt 2, 315 degrees) c. (1, 45 degrees) d. (sqrt 2, 225 degrees)

The polar coordinate is

B is correct

Step-by-step explanation:

Given:

Rectangular coordinates: (1,-1)

We need to change into polar coordinate.

Cartesian to polar change rule:

Cosine is negative and Sine is positive.

Thus, angle lie in IV quadrant.

Cartesian to polar

Hence, The polar coordinate is

step-by-step explanation:

ask goog great chance of finding the solution there

the solution of the equation is 2.23 ⇒ answer b

step-by-step explanation:

* lets revise the meaning of exponential function

- the form of the exponential function is y = ab^x, where a ≠ 0, b > 0 ,  

  b ≠ 1, and x is any real number

- it has a constant base b

- it has a variable exponent x

- to solve an exponential equation, take the log or ln of both sides,  

  and solve for the variable

* lets solve the problem

∵

- the base is 7 and the exponent is x

- insert ㏑ in both sides

∴

- use the rule

∴ x ㏑(7) = ㏑(77)

- to find x divide both sides by ㏑(7)

∴

* the solution of the equation is 2.23 to the nearest 2 decimal places