What is (3.1x10^5)(2.2x10^7) in scientific notation?

With alll of except for the 2 that i did already

To prove that angle def = angle dgf by sas, what additional information is needed? def congruent to dgf dfe congruent to dfg de congruent to dg dg congruent to gf

Simplify the algebraic expression 8y-2(y+4)