Khan Academy
Khan Academy: Completing the Square
Solve quadratic equations of the form ax^2+bx+c by completing the square. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video, or receive hints.
Illustrative Mathematics
Illustrative Mathematics: A Rei Pythagorean Triples
This task has two separate goals: the first is to solve a pair of equations, one quadratic and the other linear. The second goal is to observe that a point that lies on a circle gives rise to a Pythagorean triple. Aligns with A-REI.C.7.
Varsity Tutors
Varsity Tutors: Hotmath: Algebra Review: Solving Quadratic Equations With Square Roots
Find a quick, concise explanation for how to solve quadratic equations using square roots. An example is given and clearly explained.