Answer:
a(n)=1+(n-1)(-3)
Step-by-step explanation:
Notice there's a common difference of d=-3.
If we use the formula a(n)=a1+(n-1)d to find the nth term given the first term and the common difference, we will see that the function that describes the arithmetic sequence as a(n)=1+(n-1)(-3)
Answer: First option
Step-by-step explanation:
You have the quadratic equation given in the problem:

To find an equivalent expression you cacn factorize. Find two numbers whose sum is -13 and whose product is -30.
These numbers would be -15 and 2.
Therfore, you obtain the following equivalent expression:

If you don't want to apply the method above, you can use the quadratic formula:

Where:

When you susbstitute values you obtain that:

Then you can rewrite the equation as 