How do I write an equation for a line?

Question

A line passes through the point (3,4) and has a slope of -5. How do I write an equation for this line?

Answer 1

Equation of line: y = mx + b, where m is the slope and (0,b) is the y-intercept.

So, y = -5x + b

Since (3,4) is a point on the line, we have 4 = -5(3) + b. So, b = 19

y = -5x + 19