Please help me! The nth term of an arithmetic sequence can be defined recursively by
n doesn't equal 1.
a1 + dn
an-1 +d
an-1-d
a1 + d(n-1)

Ntriangle abc, m∠a = 35° and m∠b = 40°, and a=9. which equation should you solve to find b?

3x = 729 solve for x plz . it's urgent. will mark

Suppose a laboratory has a 30 g sample of polonium-210. the half-life of polonium-210 is about 138 days how many half-lives of polonium-210 occur in 1104 days? how much polonium is in the sample 1104 days later? 9; 0.06 g 8; 0.12 g 8; 2,070 g