Answer:

Step-by-step explanation:
Whe have the function 
To solve this equation we must factor.
To factor, we need to find the points where the function is equal to zero. So we use the quadratic formula

Where:
a = 3
b = -6
c = 2
Then

finally the correct answer is 
<span>To rewrite the expression as a multiple of a sum of two numbers with no common factor, we're supposed to find the greatest common factor between the terms and factor it out. </span>We can see that both 15 and 24 are divisible by 3. So let's factor the 3 out. Since the 3 goes into 15 five times and into 24 eight times, the expression can be rewritten like this.
15 + 24 = 3(5 + 8)
2(4z - 6 - 6) = 170 - 46
2(4z - 12) = 124 |use distributive property: a(b - c) = ab - ac
8z - 24 = 124 |add 24 to both sides
8z = 148 |divide both sides by 8
z = 18.5