standard_description: Prove that, 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 solutions.
problem_activity: Problem 1
Write 500,000 + 20,000 + 6,000 + 100 + 4 in standard and word form.
Problem 2
Write three hundred forty thousand, seventy-eight in standard and expanded form.
Problem 3
Write 73,906 in word and expanded form.


aligns: no