If 16g if a radioactive substance are present initially and 5yr later only 8g remain how much substance will be present after 9yr

9514 1404 393

  4.59 g

Step-by-step explanation:

The half-life is given as 5 years, so the amount remaining after 9 years will be ...

  remaining = initial × (1/2)^(t/(half-life))

  remaining = (16 g)×(1/2)^(9/5) ≈ 4.59 g

About 4.59 g of the substance will remain after 9 years.

answer is 8x+24

area of vanessa's patio = length × width

given, length = (3x² + 5x + 10)

width = (x² - 3x - 1)

area of vanessa's patio = (3x² + 5x + 10)(x² - 3x - 1)

= 3x²(x² - 3x - 1) + 5x(x² - 3x - 1) + 10(x² - 3x - 1)

= 3x⁴ - 9x³ - 3x² + 5x³ - 15x² - 5x + 10x² - 30x - 10

= 3x⁴ - 4x³ - 8x² - 35x - 10

hence, expression of vanessa's patio = (3x⁴ - 4x³ - 8x² - 35x - 10)