Use the diagram, which is not drawn to scale, to decide which proportions are true. a. i and iv only c. i and ii only b. ii only d. i only select the best answer from the choices provided a b c d

I think of these in terms of "short side", "long side" and "hypotenuse." The proportions will be true that equate the ratios of corresponding sides.

I is (long side of CDB)/(short side of CDB) = (long side of BDA)/(short side of BDA)

These are corresponding sides, so the proportion is true.

II is (hypotenuse of CBA)/(long side of CBA) = (long side of CBA)/(hypotenuse of CBA)

This proportion equates a value to its inverse, so is false (since the triangle has non-zero area)

III is (long side of CBA)/(short side of CBA) = (hypotenuse of CBD)/(long side of CBD)

The sides involved here are not corresponding, so this is false.

IV is (long side of CDB)/(hypotenuse of CDB)/(long side of BDA)/(hypotenuse of BDA)

These are corresponding sides, so the proportion is true.

The appropriate choice is ...

... a. I and IV only

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

step-by-step explanation:

se a cavasery6