Is 2*4 and 4*4 proportianal?

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15

Eliza wants to make $10,000 from her investments. she finds an investment account that earns 4.5% interest. she decides to deposit $2,500 into an account. how much money will be in her account after 14 years?

Which choice has the correct steps in graphing the solution set to the following inequality? -45_> 20x-5y