P(5,2) = 5!/3! = 20
in 20 ways you can give medals
The recipricol of -2/9 is 9/2, or 4 1/2
remember to change the sign (forgot to myself)
hope this helps
Answer:
Step-by-step explanation:
#22
<h3>Given </h3>
- Equation x² -4x + 1 = k(x - 4) with equal roots
<h3>To find</h3>
<h3>Solution</h3>
<u>The equation in standard form is:</u>
- x² -4x + 1 = k(x - 4)
- x² - 4x - kx + 1 + 4 = 0
- x² - (k + 4)x + 5 = 0
<u>When the quadratic equation has equal roots its discriminant is zero</u>
- D = 0
- b² - 4ac = 0
- (k + 4)² - 4*5 = 0
- (k + 4)² = 20
- k + 4 = ± √20
- k = - 4 ± √20
- or
- k = -4 ± 2√5