Answer:
Step-by-step explanation:
common difference d=3-1=2
first term a=1
an=a+(n-1)d
2n-1=1+(l-1)2
2n-1=1+2l-2
2n-1=2l-1
l=n
(i used l for number of terms)
number of terms=n

Answer:
about +–1%; between 46.5% and 47.5%
Step-by-step explanation:
Answer:
C
Steps
The A equation is impossible (even if it looks like solvable with quadratic formula)
Have a good day
Answer: 17 in.
Step-by-step explanation:
The sides of an equilateral triangle measure 16 inches. The midpoints of the sides of the triangle are joined to form another equilateral triangle with sides that are half the length of the outer triangle. This process is continued until three triangles are inscribed in the first triangle. The sum of the perimeters of all four triangles is 17 in.