## Algebra 1: Common Core (15th Edition)

$\frac{4}{c+4}=\frac{c}{c+25}$ $4(c+25)=c(c+4)$ (Cross Products Property) $4c+100=c^2+4c$ $c^2=100$ $c=10$ or $c=-10$ Check: $4/(10+4)=2/7;10/(10+25)=2/7$ $4/(-10+4)=-2/3;-10/(-10+25)=-2/3$ The equation has two solutions, -10 and 10.