Answer:
common difference d = - 4
Step-by-step explanation:
the nth term of an arithmetic sequence is
[tex]a_{n}[/tex] = a₁ + (n - 1)d
where a₁ is the first term and d the common difference
given a₁ = 24 and a₁₉ = - 48 , then
24 + 18d = - 48 ( subtract 24 from both sides )
18d = - 72 ( divide both sides by 18 )
d = - 4
