Work=speed times time (my equation to help me figure it out)
ok, 10 men take 84 days to complete a job
therefor, each man completes 1/10 of the job in 84 days
each man does 1/840 of the job per 1 day
so, if we had 5 more, or 15 men
15 times 1/840 times xdays=1 job complete
15/840 times xdays=1job
times both sides by 840/15
xdays=840/15
xdays=56
56 days it would take
Answer:
f(x) = 2x^2 - 6x - 20.
Step-by-step explanation:
(-2, 0) and (5, 0) are 2 zeroes of the function so we can write the function as
f(x) = a(x + 2)(x - 5) where a is a constant.
Now as (4, -12) is a point on the graph:
-12 = a(4 + 2)(4 - 5)
-12 = a * 6 * -1
-6a = -12
a = 2.
So f(x) = 2(x + 2)(x - 5)
f(x) = 2x^2 - 6x - 20.
X + 2 = 2x + 1
2 - 1 = 2x - x
1 = x
x = 1
