hi
u0 = 64 with u(n+1) = un *0.75
u3 = 64 *0.75^3 = 27
sum is : 64 * ( 0.75^4 -1) / 0.75-1 = 175
manual proof : 64 + 48+36+27 = 175
It’s 16 because Ik I did it before so do y worry
Answer:

Step-by-step explanation:
You can multiply 6p + m = 9 by -2 so you gonna have -12p - 2m = -18 then you can say : -12p - 2m = -18 ⇒ -8p = -10 ⇒ p = 10/8 ⇒ p = 1.25
4p + 2m = 8
so now you can find the m : 6 * 1.25 + m = 9 ⇒ 7.5 + m = 9 ⇒ m = 9 - 7.5 ⇒ m= 1.5 :)))
i hope this is helpful
have a nice day