The product is 18n^2-48n-12n+32 which simplifies to 18n^2-60n+32. I got this using the FOIL method (First, Outer, Inner, Last)
The value of 3 in 630 is ten
First, distribute the parenthesis:
(2x - 4) (4x - 5) = 8x - 20
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| |
2x * 4x, 4 * 5
Then you add 20 to both sides
8x - 20 = 0
+20 +20
8x = 20
Then you divide both sides by 8

x = 2.5
I think I did that right... I don't quite remember what a solution set is
Answer: f(x) = -3| x - 1 | is really just f(x) = -3| x - 1 | + 0.
now, what value of "x" makes the absolute value expression to 0?
well, let's just set it to 0 and check,
x - 1 = 0
x = 1
so if "x" ever becomes 1, the | x - 1| will turn to 0, therefore, the vertex is at
f(x) = -3| (1) - 1 | + 0 --------------> ( 1, 0 )