Question

please help!
For each function, give one zero. Most of the functions have more than one zero, but just pick one.
Function: y=(x-4)(x+6)
-6
5
none
-2
-1
1
4
which one of those would fit for the equation? I think it's 4 but I'm really struggling here. Can somehow help?

Answer 1

Yes, 4 will give you a zero
What you want is the value of x so that the y value is 0
y = (x-4)(x+6)
If you are multiplying a bunch of numbers, if one of them is zero, no matter how many
you are multiplying or what the value of the others are, the result will be zero.
e.g. 6x9x7x12x456.36<b>x0x</b>78 = 0

so if you have y = ..... and the expression is factored like your given equation, all you have to do is set all the factors equal to zero. Each one will give you a solution for x that will make the function zero

e.g.
(x-4) = 0
x-4 = 0
x = 4 <----- a solution

also
x+6 = 0
x = -6 <------ another solution, it is in your list

Answer 2

The Jishka teachers are so great. Thank you