Equations in follow a specific format.
y=mx+b
In the above formula,
m represents the and
b the of the line. The line has a slope of
-3, which means that we can substitute
-3 for
m.
y=mx+b⇒y=-3x+b
To write a complete equation for this line, we also need to determine the
y-intercept,
b. We can do this by substituting the given point,
(1,4), into the equation and solving the resulting equation for
b. y=-3x+b
4=-3⋅1+b
4=-3+b
7=b
b=7
Now that we have both the slope and the
y-intercept, we can write the equation.
y=-3x+7