Advanced Math practice question

Answer: 4

Write 32 as a power of 2: 32 = 2⁵. Then 2ˣ⁺¹ = 2⁵, so the exponents are equal: x + 1 = 5 and x = 4. Check: 2⁵ = 32.

Common wrong answers

If you answered 5

5 is the exponent that makes 2 to the power equal 32 — but the exponent here is x + 1, so x = 5 − 1 = 4.

If you answered 16

16 is 32/2, dividing instead of reasoning about exponents. 2ˣ⁺¹ = 2 · 2ˣ, so 2ˣ = 16 and x = 4.

If you answered 31

31 is 32 − 1, treating 2ˣ⁺¹ as if it were 2 + x + 1. The x is an exponent.

More Advanced Math questions

• Hard
  A population of bacteria doubles every 3 hours. If it starts at 500, which function models the population P af…
• Hard
  How many real solutions does x² + 4x + 5 = 0 have?
• Hard
  A car worth $20,000 loses 15% of its value each year. What is its value after 2 years?
• Hard
  An investment of $1,000 grows at 6% per year, compounded annually. Which expression gives its value after t ye…
• Hard
  If f(x) = x² − 1 and g(x) = x + 2, what is g(f(3))?
• Hard
  The parabola y = x² − 8x + 12 crosses the x-axis at two points. What is the x-coordinate of the vertex?