A line passes through the point , 8−1 and has a slope of −3/4 . Write an equation in slope-intercept form for this line.

Respuesta :

Answer: y = -3/4 + 5

Slope-intercept form: y = mx + b
                                           ^       ^
                        m is the slope    b is the y-intercept

Since -3/4 is the slope of the line, the equation is y = -3/4x + b.

Solve for b, the y-intercept, by substituting in 8 for x and -1 for y.
y = -3/4x + b                   Substitution
-1 = -3/4(8) + b                Multiply -3/4 and 8
-1 = -6 + b                       Add 6 to both sides
b = 5                               y-intercept!

Substitute in the y-intercept, 5, back into y = -3/4 + b.
y = -3/4 + 5