Question

please answer this q20

Answer 1

Now, we know that P and Q trisects the line AB. We have the coordinates of A and B and we also know the ratio in which Q divides AB as it is 2:1.

Now by using section formula, we can find the coordinates of Q.
x= m1x2 + m2x1 / m1 + m2
y = m1y2 + m2y1/ m1 + m2

By doing this, we get Q's coordinates which are (4,-5).

Now, we have to find the coordinates of P. For this, we can use midpoint formula as it is the midpoint of A and Q.

So, 
x = x1+x2 / 2
y= y1+y2 / 2

By doing this, we get the coordinates of P which are (3,-2).

Now, substitute the values of x and y into the equation 2x-y+k = 0.
You will get 6+2+k=0
i.e, 8+k=0

This means, k= -8.

Answer 2

$\huge\star\underbrace {\mathtt\purple {A}\mathtt\purple {n}\mathtt\purple {s}\mathtt\purple {w}\mathtt\purple {e}\mathtt\purple {r}}\star\:$

Now, we know that P and Q trisects the line AB. We have the coordinates of A and B and we also know the ratio in which Q divides AB as it is 2:1.

Now by using section formula, we can find the coordinates of Q.

• x= m1x2 + m2x1 / m1 + m2
• y = m1y2 + m2y1/ m1 + m2

By doing this, we get Q's coordinates which are (4,-5).

Now, we have to find the coordinates of P. For this, we can use midpoint formula as it is the midpoint of A and Q.

So, 

• x = x1+x2 / 2
• y= y1+y2 / 2

By doing this, we get the coordinates of P which are (3,-2).

Now, substitute the values of x and y into the equation 2x-y+k = 0.

You will get 6+2+k=0

i.e, 8+k=0

This means, k= -8.