(a(i))[1]
Determine the value of $a$.
(a(ii))[1]
Determine the value of $b$.
(b)[2]
Work out the value of $x$.
(c(i))[1]
State the mathematical name of the line $BC$.
(c(ii))[1]
Explain why angle $ABC$ is $90^\circ$.
(c(iii))[2]
Determine the value of $x$.
(c(iv))[2]
Determine the value of $y$.