18+
• (6, 19.5)
• (5, 17.5)
• (4, 15.5)
• (3, 13.5)
• (2, 11.5)
10+
(1.9.5)
-
1
2
3
4
5
6
7
8 9
n
an=-23+2(n-1)
da,=-2.75 +0.5(n-1)
da, = 9.5+2(n-1)
dan=11+0.5(n-1)

I will answer this for you if you put this into understandable terms.

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