(a)[1]
Fill in the table of values for $y=\dfrac{x}{20}(x^2-10)$.
(b)[2]
On axes using a scale of $2\text{ cm}$ to $1$ unit on both axes, sketch the graph of $y=\dfrac{x}{20}(x^2-10)$ for $0 \le x \le 5$.
(c)[2]
By drawing a tangent, estimate the gradient of the curve at the point where $x=2.5$.
(d)[2]
Use the graph to solve $\dfrac{x}{20}(x^2-10)=0$ for $0 \le x \le 5$.
(e(i))[2]
Find the equation of the straight line $L$ that is used with the graph of $y=\dfrac{x}{20}(x^2-10)$ to solve $x^3+10x-80=0$.
(e(ii))[1]
Draw the graph of line $L$ on the grid.
(e(iii))[1]
Hence solve the equation $x^3+10x-80=0$ for $0 \le x \le 5$.