Mathematics
The points P(-2, 4), Q(3, -1) and R(6, 2) are the vertices of a triangle. Δ PQR is reflected in y-axis to form ΔP'Q'R'. Find the co-ordinates of P', Q' and R'.
Reflection
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Answer
We know that,
Rule to find reflection of a point in y-axis :
Retain the ordinate i.e. y-coordinate.
Change the sign of abscissa i.e. x-coordinate.
∴ P(-2, 4) ⇒ P'(2, 4)
∴ Q(3, -1) ⇒ Q'(-3, -1)
∴ R(6, 2) ⇒ R'(-6, 2)
The coordinates of the vertices of ΔP'Q'R' are P'(2, 4), Q'(-3, -1), R'(-6, 2).
Hence, coordinates of the vertices of ΔP'Q'R' are P'(2, 4), Q'(-3, -1), R'(-6, 2).
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