Answer:
6.28 cm
Step-by-step explanation:
The formula for the circumference of a circle with radius r is C = 2*pi*r.
If we let pi = 3.14 and r = 1 cm, then the circumference of this circle is
C = 2(3.14)(1 cm) = 6.28 cm
Take the coefficient of the x-term, half it, then square that. add this to both sides
x² + 16x. coefficient of x is 16. half of 16 is 8. 8²=64
x² + 16x + 64 =64. this is your answer but to continue
x² + 16x + 64 = 64
(x+8)² = 64
x+8 = ✓64
x+ 8 = ±8
x = 0 or -16