MATH SOLVE

3 months ago

Q:
# Vladimir says that the equation of the line that passes through points (-5,-3) and (10,9) is y=4/5x+1. Robyn says that the line passes through the points (-10,-7) and (-15,-11). Who is correct? a)only Vladimir b)only Robyn c)both Vladimir and Robyn d)neither Vladimir nor Robyn

Accepted Solution

A:

the slope given by Vladmir's points = (9--3)/10--5) = 12/15 = 4/5

so its equation is

y - y1 = (4/5)(x - x1) where (x1,y1) = (10,9) giving:-

y - 9 = (4/5)(x - 10)

y = 4/5 x =1 which is the required equation

So Vladimir is right.

Testing if Robyn is right:-

Plug in his values:-

-7 = 4/5*-10 + 1

-7 = -7 so that point is on the line

-11 = (4/5) * -15 + 1

-11 = -11 so this point is also on the line

Answer:- c) Both are right

so its equation is

y - y1 = (4/5)(x - x1) where (x1,y1) = (10,9) giving:-

y - 9 = (4/5)(x - 10)

y = 4/5 x =1 which is the required equation

So Vladimir is right.

Testing if Robyn is right:-

Plug in his values:-

-7 = 4/5*-10 + 1

-7 = -7 so that point is on the line

-11 = (4/5) * -15 + 1

-11 = -11 so this point is also on the line

Answer:- c) Both are right