Question

Find the coordinates of the point R if S(-1, 13) is
the midpoint of the Ilne PR with P having
coordinates (4,12)​

Answer 1

Step-by-step explanation:

Answer

Correct option is

A

5

8

,

5

21

Given that the point R(x,y) divides the line segment PQ joining the points P(x

1

,y

1

)=(1,3) & Q(x

2

,y

2

)=(2,5) in a ratio such that

PQ

PR

=

5

3

i.e PR<PQ.

⇒R divides PQ internally.

Here

PQ

PR

=

5

3

⇒

PR

PQ

=

3

5

⇒

PR

PR+RQ

=

3

5

⇒

PR

RQ

=

3

2

⇒

QR

PR

=

2

3

∴m:n=3:2

∴ By the section formula, we have

x=

m+n

nx

1

+mx

2

& y=

m+n

ny

1

+my

2

i.e x=

2+3

2×1+3×2

=

5

8

and y=

2+3

2×3+3×5

=

5

21

Therefore, x=

5

8

;y=

5

21

Hence, option A is the correct answer.