Question

A line passes through (9, –9) and (10, –5). a. Write an equation for the line in point-slope form. b. Rewrite the equation in standard form using integers

Answer 1

-5+9= 4
10-9=1
The slope is 4 so the equation would be y+5=4(x-10)

Answer 2

(9,-9)(10,-5)
slope = (-5 - (-9) / (10 - 9) = 4/1 = 4

y - y1 = m(x - x1)....there can be 2 answers for this one...

using (9,-9)..
y - (-9) = 4(x - 9) =
y + 9 = 4(x - 9) <== this one

using (10,-5)
y - (-5) = 4(x - 10) =
y + 5 = 4(x - 10) <== this one

y + 5 = 4(x - 10)
y + 5 = 4x - 40
y = 4x - 40 - 5
y = 4x - 45
-4x + y = -45
4x - y = 45 <== standard form