Use substitution to solve the linear system of equations.
5x - y = 15
-10x + 2y = -30

Julia chooses a card at random from her set of cards. what is the probability that the card is labeled cat or hamster?

1. writing an equation for an exponential function by 2. a piece of paper that is 0.6 millimeter thick is folded. write an equation for the thickness t of the paper in millimeters as a function of the number n of folds. the equation is t(n)= 3. enter an equation for the function that includes the points. (-2, 2/5) and (-1,2)

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