3. Given a system of two equations in two variables, replacing one equation by the sum of that equation and a multiple of the other produces a system with the same solution. Show why this is true by solving the system of equations given. Justify the reason for each step. HINT: Use addition property of equality and multiplication property of equality in your answers. (8 points: 1 point for each question) 5x + 2y = 7 3x – y = 2 To solve the system using elimination, first multiply the bottom equation by 2. Write the new system of equations. (1 point) Why is this multiplication allowed? (1 point) What variable will be eliminated when the equations are combined after the multiplication? (1 point) Next, add the equations together. Your answer should be a single equation with one variable. (1 point) Why can you add the equations? (1 point) Solve the equation for x. (1 point) Substitute x back into one of the equations to solve for y. (1 point) What is the solution to the system of equations? (1 point)

Part a what is the area of triangle i? show your calculation. part b triangles i and ii are congruent (of the same size and shape). what is the total area of triangles i and ii? show your calculation. part c what is the area of rectangle i? show your calculation. part d what is the area of rectangle ii? show your calculation. part e rectangles i and iii have the same size and shape. what is the total area of rectangles i and iii? show your calculation. part f what is the total area of all the rectangles? show your calculation. part g what areas do you need to know to find the surface area of the prism? part h what is the surface area of the prism? show your calculation. part i read this statement: “if you multiply the area of one rectangle in the figure by 3, you’ll get the total area of the rectangles.” is this statement true or false? why? part j read this statement: “if you multiply the area of one triangle in the figure by 2, you’ll get the total area of the triangles.” is this statement true or false? why?

The equation |pl = 2 represents the total number of points that can be earned or lost during one turn of a game. which best describes how many points can be earned or lost during one turn? o o -2 2 oor 2 -2 or 2 o

The equation of a parabola is given. y=18x2+4x+20 what are the coordinates of the focus of the parabola?