Find that 10th term of each arithmetic sequence 1). a4=12 and a7=20.4 2.) a3=37 and a17=-12 3.) a13=-5 and a18=-51 4.) a25=18 and a41=62

1.

 4th term  = a1 + 3d = 12  (where a1 = first term and d = common difference.)

7th term = a1 + 6d = 20.4

subtract  4th from 7th term, we get:-

3d = 8.4

d =  2.8

So 10th term = 7th term + 3(common difference)

= 20.4 + 3(2.8)

= 20.4 + 8.4

= 28.8    (answer)

All the  rest can be answered in  the same way.

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

the ratio would be 4: 3, the four being for jackson, and the three being not for him.