No this is not a function because 4 is used twice on the y side
Step-by-step explanation:
x(x + 7) = 0
By Zero Product rule,
either x = 0 or (x + 7) = 0.
=> x = 0 or x = -7.
Ok let’s solve it
5(x-2)^2-20=0
first let’s foil (x-2)
5(x^2-4x+4) -20=0
now distribute the 5
5x^2 -20x +20 -20 = 0
combine like terms
5x^2-20x=0
take the gcf
5x(x-4)=0
x=0, 4
solutions are (4,0) and (2, -20) because the original vertex form a(x-h)^2+k
Answer:

Step-by-step explanation:
First you need to find how many marbles there are in total, so 3+8+2= 13
The probability of the marble being red is
then
Hope this helps! :)