I need good, clearly explaining for this qustion.

the radius is 2 times the diameter.

step-by-step explanation:

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

it is a horizontal line.

graphs that are inverses of each other are graphs where their slopes are reciprocals of each other for example say you have an original equation of y=2x. the inverse of that graph would be y=-1/2(x). also when you see a graph where the original and the inverse is graphed the angle around intersection is 90 degrees.