Question

What is Y equals 3X +20

Answer 1

You can’t solve an equation with two variables. The simplest it gets is Y=3x+20 or X=1/3Y - 6 2/3
Or maybe you’re asking what the equation is? Y=mx+b is the slope intercept form.

Answer 2

y = 3x + 20

This is an equation, in slope-intercept form, which represents a the placement of a line. The 3 in the equation represents the slope of the line, and the 20 represents the y-intercept.