Step-by-step explanation:
[tex]x - 23 = 57 \\ x = 57 + 23 \\ x =80 \\ \\ \frac{2}{3}x = 7 \\ ( \frac{3}{2}) \frac{2}{3}x = 7( \frac{3}{2}) \\ x = \frac{21}{2} [/tex]
