Tatiana wrote the steps that are commonly used to solve a system of equations with two variables. Which steps are correct? Check all that apply. Multiply the value of the first variable by one of the original equations to solve for the second variable. Use multiplication to write an equivalent equation with an opposite term. Solve for one of the variables. Write the opposite of one variable to solve for the other variable. Add the equivalent system of equations to eliminate a variable. Write the solution as an ordered pair. Substitute the value of the known variable into one of the original equations to solve for the unknown variable.