Question

what is the equation, in slope- intercept form, of the line that contains the points (-3,4) and (5,7)

Answer 1

Answer:

y = $\frac{3}{8}$ x + $\frac{41}{8}$

Step-by-step explanation:

the equation of a line in slope- intercept form is

y = mx + c ( m is the slope and c the y-intercept )

To calculate the slope use the gradient formula

m = ( y₂ - y₁ ) / ( x₂ - x₁ )

with (x₁, y₁ ) = (- 3, 4) and (x₂, y₂ ) = (5, 7)

m = $\frac{7-4}{5+3}$ = $\frac{3}{8}$, hence

y = $\frac{3}{8}$ x + c ← is the partial equation

To find c substitute either of the 2 points into the partial equation

using (5, 7 ), then

7 = $\frac{15}{8}$ + c ⇒ c = 7 - $\frac{15}{8}$ = $\frac{41}{8}$

y = $\frac{3}{8}$ x + $\frac{41}{8}$ ← equation in slope-intercept form