Find the 15th term of the arithmetic sequence 2x+7, 6x+11, 10x+15,

a15 = 58x + 63

Step-by-step explanation:

number of terms (n) = 15

first term (a1) = 2x + 7

second term (a2) = 6x + 11

common difference (d) = a2-a1 = 6x + 11 - (2x + 7)

                                                   = 6x + 11 - 2x - 7

                                                   = 4x + 4

                                                   = 4(x + 1)

15th term (a15) = ?

                                  equation :

                  a15 = a1 + (n - 1) × d

                  a15 = 2x + 7 + (15 - 1) × 4(x + 1)

                  a15 = 2x + 7 + 14 × 4 × (x + 1)

                  a15 = 2x + 7 +  56(x + 1)

                  a15 = 2x + 7 +  56x + 56

                  a15 = 58x + 63

she played for 18.75 hours.

step-by-step explanation:

if she played 2/4 of a hour on tuesday. and there is 60 minutes in an hour and 60 divided by 4 is 7.5. and she played 2/4 of an hour on thursday then again 60 divided by 4 is 7.5, you add 7.5+7.5=56.25. now you have to do 1/4 of an hour, it equals 3.75. now you have to add them all up. 3.75+7.5+7.5=18.75

i hope this and i hope you get it right. it took me a while to get this done for you. : )