Approximately 25 days. In this unit, students deepen their algebraic reasoning as they write and solve equations of the forms px+q = r and p(x+q) = r and inequalities of the forms px+q > r and p(x+q) < r . Students also work with equivalent expressions that are more complex than what they have seen previously. This builds on grade 6 work with equations of the form p+x = q or px=q and with simpler equivalent expressions. Students will build on this work in grade 8 when they solve equations that have a variable on both sides of the equal sign and when they work with systems of equations.