Answer:
coordinates of R(x,y) is R(6,-2).
Step-by-step explanation:
We have given the coordinates of rectangle PQRS as: P(-1,2), Q(2,4), R(x,y), and S(3,-4).
We know the slope formula:
Slope =
Now, by applying slope formula
Slope of PQ =
=
Slope of RS =
Slope of QR =
We know that, slopes of PQ and RS are equal because these are parallel to each other.
Slope of PQ = Slope of RS
=
2(3-x) = 3(-4-y)
6-2x = -12-3y
2x-3y = 18...........equation(1)
Slopes of perpendicular lines are negative reciprocal. Therefore,
Slope of PQ =
=
=
On cross multiplication,
2(y-4) = 3(-x+2)
2y-8 = -3x+6
3x+2y = 14.............equation(2)
Now, multiplying equation(1) by 2 and equation(2) by 3 and then equations are adding..
So, 4x-6y=36
9x+6y=42
________________
13x=78
x=6
Putting the value of x in equation(2)
18+2y=14
2y=-4
y=-2
So, coordinates of R(x,y) is R(6,-2).