What does the word variable mean in mathematics in your own words?

The minimum wage in washington has been increasing over the last ten years. years 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 washington state minimum wage $6.50 $6.72 $6.90 $7.01 $7.16 $7.35 $7.63 $7.93 $8.07 $8.55 $8.55 a) find the linear regression equation for the minimum wage in washington using this data ( x  0 in 2000). round to the thousandths. b) what is the slope? specifically, what does the slope represent in the real world context? c) what is the y-intercept? specifically, what does the y-intercept represent in the real world context? d) write your equation as a function of x. e) if you do not earn a college degree and you are earning minimum wage in 2020, what do you predict you will be earning per hour with the linear regression equation? f) if the trend continues, when will the minimum wage be $15 an hour? 3. why are your answers to #1d and #2a above different? which do you think is more accurate (#1 or #2) and why

In the polynomial below, what number should replace the question mark to produce a difference of squares? x2 + ? x - 36

What is the total surface area of this square pyramid?