Chapter 7 - Section 7.6 - Proportions and Problem Solving with Rational Equations - Exercise Set - Page 539: 42

$x=3$

$15*(1/x)+(9x-7)/(x+2)=9$ $15/x +(9x-7)/(x+2)=9$ $[(x)(x+2)](15/x +(9x-7)/(x+2)=9)$ $15(x+2)+(9x-7)(x)=9(x)(x+2)$ $15x+30+9x^2-7x=9(x^2+2x)$ $9x^2+8x+30 = 9x^2+18x$ $8x+30 = 18x$ $30 =10x$ $30/10 = 10x/10$ $3=x$ $15*(1/x)+(9x-7)/(x+2)=9$ $15*(1/3)+(9*3-7)/(3+2)=9$ $15/3 +(27-7)/(5)=9$ $5 +20/5 = 9$ $5+4=9$ (true)