By Kimberly Amadeo. Definition: Silicon Valley is the center for innovative technology companies. It's located in the are around San Francisco, California.It's home to 2,000 tech companies, the densest concentration in the world. This proximity to suppliers, customers, and cutting edge research gives each a competitive advantage.ilicon Valley Companies. The most well-known Silicon Valley companies include Adobe, Apple, Cisco, eBay, Facebook, Google, Hewlett-Packard, Intel, Intuit, Netflix, Oracle, Salesforce.com, Tesla, Twitter, Yahoo! and Zynga.
Math definition of Substitution: Substitution - A strategy for solving systems of equations that include solving for one variable and using that solution to find the other variable. 1  Subject : Math.  Topic : Algebra 2.
truncate - replace a corner by a plane geometry - the pure mathematics of points and lines and curves and surfaces interchange, substitute, replace, exchange - put in the place of another; switch seemingly equivalent items; the con artist replaced the original with a fake Rembrandt; substitute regular milk with fat-free milk; synonyms can be interchanged without a changing the context's meaning 2. truncate - approximate by ignoring all terms beyond a chosen one; truncate a series