Advanced MathMediumA difference that is constant
Advanced Math practice question
For every value of x, the expression (x + 2)(x + 3) − x(x + 5) is equal to the same constant. What is that constant?
Answer: 6
(x + 2)(x + 3) = x² + 5x + 6 and x(x + 5) = x² + 5x. Their difference is 6.
Common wrong answers
- If you answered 0
- 0 would need the constants to cancel too; only the x² and 5x terms cancel.
- If you answered 5
- 5 is the coefficient that cancels, not what remains.
- If you answered -6
- −6 has the wrong sign (subtracting in the wrong order).
More Advanced Math questions
- Medium
What are the solutions to x² − 5x + 6 = 0? - Medium
The graph of f(x) = (x − 3)² + 4 is a parabola. What are the coordinates of its vertex? - Medium
If x² − 2x − 8 = (x + 2)(x − a), what is the value of a? - Medium
If √(x + 5) = 4, what is the value of x? - Medium
If f(x) = x + 3 and g(x) = 2x, what is f(g(4))? - Medium
What are the solutions to x² + 6x + 8 = 0?
Not affiliated with the College Board. SAT is a trademark of the College Board.