The regression equation y = a + bx represents the line that best fits a set of (x,y) data points. You can google keywords scatterplot regression line best fit to see examples and images.
In the equation for this line, symbol b is a constant that represents the rate at which y is changing, with respect to increasing x by 1 unit. Symbol a is a constant that represents the value of y when x is zero. Graphically speaking, b is the slope of the line, and a is the y-intercept of the line (that is, the line's vertical positioning on an xy-coordinate grid).
The chart you posted seems to indicate that someone has already done the regression (i.e., they have already determined the values of a and b) because it is titled regression results, but I do not understand the given numbers.
I do see a number for each model in the chart labeled "Constant", but it's not clear to me that it is the value of a or b. As I do not understand the context of the data, I cannot recognize any rate.
The numbers inside parentheses are noted as errors; it seems strange that the error listed for each "Constant" is about 2 to 2.5 times larger than the value itself.
I regret that I do not understand the given scenario.
