Answer:
x = 7
Step-by-step explanation:
since we know y = 4, we can plug this into the equation to find x
8x - 2y = 48
8x - 2(4) = 48
8x - 8 = 48
8x = 56
x = 7
In step two he flipped the fraction back to how it was originally but he was supposed to leave it improper in order to multiply
Easy
remember
x^-m=1/(x^m)
so
f(-1)=4*7^-1=4*(1/(7^1))=4*(1/7)=4/7
f(2)=4*7^2=4*49=196