Question

Someone please help me.

Answer 1

If N is midpoint of QR, then you must use the formula of a midpoint:

$M\left(\dfrac{x_1+x_2}{2},\ \dfrac{y_1+y_2}{2}\right)$

We have Q(0, 2b) and R(2c, 0). Substitute:

$x=\dfrac{2c+0}{2}=\dfrac{2c}{2}=c\\\\y=\dfrac{2b+0}{2}=\dfrac{2b}{2}=b$

Answer: (c, b)