# How do you find the formula for #a_n# for the arithmetic sequence #a_1=100, d=-8#?

##### 1 Answer

Jun 4, 2017

#### Explanation:

#"for the standard arithmetic sequence"#

#a,color(white)(x)a+d,color(white)(x)a+2d,....,a+(n-1)d#

#"the nth term "=a+(n-1)d#

#"here " a=a_1=100" and " d=-8#

#rArra_n=100-8(n-1)#

#color(white)(rArra_n)=100-8n+8#

#color(white)(rArra_n)=108-8n#