Virginia es 8 años menor que Sonia y hace 10 años la edad de Virginia era 3/4 de la edad que Sonia tenía ¿cuál es la edad actual de Sonia?​

Suppose you are an avid reader and are looking to save money on the cost of books instead of paying about $20 for each book, you decide to look into purchasing a kindle for $120 you can purchase e-books for about $5 each 1. find the slope-intercept equation for the cost of the hard copy of books using x to represent the number of books 2. find the slope-intercept equation for the cost of the kindle with cost of e-books using x to represent the number of books

Construct the graph that models the given situation

Which property was used to simplify the expression? 3c+9 +4c=3c+4c+9