Chernobyl is the site of a nuclear disaster that happened in 1986.
Due to the slow decay of radioactive elements, the site is still extremely dangerous today.
In 2016, engineers covered the main damaged nuclear reactor with a giant concrete cap, as shown below:
The cross section of this cover can be modelled with the parametric equations:
\[x = 8\left( t + 10 \right)\ ,\ y = 100 – t^{2}\ ,\ – 19 \leq t \leq 10\]
a) Find the Cartesian equation of this model.
[3 marks]
b) The width of the cap, according to the model.
[2 marks]
