The problem is to find the size of angle DAB in a quadrilateral ABCD. We are given that angle D = $89^{\circ}$, angle C = $90^{\circ}$ (right angle), and angle B = $75^{\circ}$.

1. Problem Description

The problem is to find the size of angle DAB in a quadrilateral ABCD. We are given that angle D = $89^{\circ}$, angle C = $90^{\circ}$ (right angle), and angle B = $75^{\circ}$.

2. Solution Steps

The sum of the interior angles of a quadrilateral is $360^{\circ}$. Therefore,

$angle A + angle B + angle C + angle D = 360^{\circ}$

$angle DAB + 75^{\circ} + 90^{\circ} + 89^{\circ} = 360^{\circ}$

$angle DAB + 254^{\circ} = 360^{\circ}$

$angle DAB = 360^{\circ} - 254^{\circ}$

$angle DAB = 106^{\circ}$

3. Final Answer

The size of angle DAB is $106^{\circ}$.