Solve {l}{C=2pir}{C=2*pi*0.3}{C=7.88m}

$$\left. \begin{array} { l } { C = 2 \pi r } \\ { C = 2 \times \pi \times 0.3 } \\ { C = 7.88 m } \end{array} \right.$$

Solve for C, r, m

$$r=0.3$$

$$C = \frac{3 \pi}{5} \approx 1.884955592$$

$$m=\frac{15\pi }{197}\approx 0.239207562$$

Short Steps Using Substitution

Substitute 2\pi r for C in the second and third equation.

$$2\pi r=2\pi \times 0.3 2\pi r=7.88m$$

Solve these equations for r and m respectively.

$$r=\frac{3}{10} m=\frac{50}{197}\pi r$$

Substitute \frac{3}{10} for r in the equation m=\frac{50}{197}\pi r.

$$m=\frac{50}{197}\pi \times \frac{3}{10}$$

Calculate m from m=\frac{50}{197}\pi \times \frac{3}{10}.

$$m=\frac{15}{197}\pi$$

Substitute \frac{3}{10} for r in the equation C=2\pi r.

$$C=2\pi \times \frac{3}{10}$$

Calculate C from C=2\pi \times \frac{3}{10}.

$$C=0.6\pi$$

The system is now solved.

$$C=0.6\pi r=\frac{3}{10} m=\frac{15}{197}\pi$$