(a)
$$ \alpha = \beta+40^\circ $$
$$ \alpha+\beta = 180^\circ $$
$$ \alpha = 110^\circ \qquad \beta = 70^\circ $$
(b)
$$ \alpha = \beta $$
$$ \alpha+\beta = 116^\circ $$
$$ \alpha = \beta = 58^\circ $$
(b)
$$ \alpha = 37^\circ $$
$$ \beta = \alpha = 37^\circ $$
$$ \gamma = 180^\circ-\alpha = 143^\circ $$
(d1)
$$ \alpha = 2\beta $$
$$ \alpha+\beta = 180^\circ $$
$$ \alpha = 120^\circ \qquad \beta = 60^\circ $$
(d2)
$$ \alpha = 3\beta $$
$$ \alpha+\beta = 180^\circ $$
$$ \alpha = 135^\circ \qquad \beta = 45^\circ $$