tmua 2019 Q6

tmua · Uk · paper1 1 marks Circles Circles Tangent to Each Other or to Axes

The circles with equations
$$\begin{aligned} &(x+4)^2 + (y+1)^2 = 64 \quad \text{and} \\ &(x-8)^2 + (y-4)^2 = r^2 \quad \text{where } r > 0 \end{aligned}$$
have exactly one point in common. Find the difference between the two possible values of $r$.

..... 8

The circles with equations

$$\begin{aligned}
&(x+4)^2 + (y+1)^2 = 64 \quad \text{and} \\
&(x-8)^2 + (y-4)^2 = r^2 \quad \text{where } r > 0
\end{aligned}$$

have exactly one point in common.
Find the difference between the two possible values of $r$.

Paper Questions

Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 Q11 Q12 Q13 Q14 Q15 Q16 Q17 Q18 Q19 Q20