The frequency is how often something occurs. Here 15. It occurred 15 times that the participants scored in the interval given.
The relative frequency (expressed as a percent) looks at how often something occurred relative to the overall occurrences. Here 15/60 = 1/4 = 25%
The relative frequency is 25%
Use FOIL and simply, First times First, Outside times Outside, Inside times Inside, Last times Last.
(3x+5)(4x-1)
3x * 4x = 12x²
3x * -1 = -3x
5 * 4x = 20x
5 * -1 = -5
12x² - 3x + 20x - 5
Now simplify by adding -3x to 20x and get:
12x² + 17x - 5
Amplitude : 2/3
Period : 3pi/2
X² + 4x + 4 = 25
(x+2)² = 25
x + 2 = <span>±5
x + 2 = -5 or x + 2 = 5
x = -5 -2 x = 5 - 2
x = -7 x = 3
</span><span>The solutions are x=-7 and x=3</span>
