Answer:
3 2/4
Step-by-step explanation:
8x^3+1 is the answer because we can rewrite it as this : (2x)^3 + 1^3
Sum of 2 perfect cubes
a³+b³=(a+b)(x²-xy+y²)
so
x³+4³=(x+4)(x²-4x+16)
set each to zero
x+4=0
x=-4
the other one can't be solveed using conventional means
use quadratic formula
for
ax^2+bx+c=0
x=
for x²-4x+16=0
x=
x=
x=
x=
x=
x=
the roots are
x=-4 and 2+2i√3 and 2-2i√3
25% = 0.25
70*0.25 = 17.50
Subtract 17.50 from 70
70-17.50 = $52.50