Quadratic EquationsStep 1 of 3
Question
Solve 25x² − 49 = 0.
x = 7/5
x = −7/5
How should 25x² − 49 be written as a difference of squares?
What you will learn
Recognise a difference of squares, use the zero-product rule, and preserve both positive and negative solutions.
Common mistake to avoid
Taking only the positive square root loses a valid solution and usually loses one mark in a board-style question.
Make this mistake visibleHelpful?