Brenda pays $30 for materials to make earrings. She makes 10 earrings and sells 7 for $5 and 3 for $2. Write a numerical expression to represent this situation and then find Brenda's profit?

Type the correct answer in the box. consider the system of linear equations below. rewrite one of the two equations above in the form ax + by = c, where a, b, and c are constants, so that the sum of the new equation and the unchanged equation from the original system results in an equation in one variable.