Caballero purchases a toy car for $6 3/4 and spends $2 1/2 on ice cream. If he has a starting balance of $10, how much money does caballero have left?

Based on what i know about mean, this doesn't add up.

Which equation can be used to solve for the unknown number? seven less than a number is thirteen. n-7=13 7-n=13 n+7=13 n+13=7

Evaluate the discriminant of each equation. tell how many solutions each equation has and whether the solutions are real or imaginary. x^2 - 4x - 5 = 0