Solve Quadratics
1. Stating the problem:
Solve the system:
$$25x^2=16$$
$$\frac{x}{x+2}=\frac{x+3}{5x+11}$$
2. Solve the first equation:
$$25x^2=16 \implies x^2=\frac{16}{25} \implies x=\pm \frac{4}{5}$$
3. Solve the second equation:
Start with:
$$\frac{x}{x+2}=\frac{x+3}{5x+11}$$
Cross multiply:
$$x(5x+11) = (x+3)(x+2)$$
Expand both sides:
$$5x^2 + 11x = x^2 + 5x + 6$$
Bring all terms to one side:
$$5x^2 + 11x - x^2 - 5x - 6 = 0$$
Simplify:
$$4x^2 + 6x - 6 = 0$$
Divide entire equation by 2:
$$2x^2 + 3x - 3 = 0$$
4. Solve quadratic:
Use quadratic formula:
$$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$
with $a=2$, $b=3$, $c=-3$
Calculate discriminant:
$$\Delta = 3^2 - 4 \cdot 2 \cdot (-3) = 9 + 24 = 33$$
Compute solutions:
$$x= \frac{-3 \pm \sqrt{33}}{4}$$
Final answers:
From first equation:
$$x = \pm \frac{4}{5}$$
From second equation:
$$x = \frac{-3 + \sqrt{33}}{4}$$ or $$x = \frac{-3 - \sqrt{33}}{4}$$