X2 - 2x + 9x - 18
X2 + 7x - 18
28 men are needed to paint the room in 3 hours
<h3><u>Solution:</u></h3>
Given that it takes 12 hours for 7 men to paint a room
We are asked to find number of men required to paint the room in 3 hours
Recognize, "paint the room" is 1 task. One job.
7 men -------- 12 hours ------ 1 job
(7/7) = 1 men ------- 12 x 7 (84) ------- same 1 job
The one men is rate is 84 hours to do the job
We can express this as 1/84 jobs per hour, the one-person rate
Now lets find how many men needed to paint the room in 3 hours
Let the required number of men for 3 hours be "a"
The rates of each person is simply additive.
corresponds to rate x hours = jobs and "a" is a variable for how many men
Thus 28 men are needed to paint the room in 3 hours
Answer:
The system of equations is:
x + y = 15
xy = 15
Step-by-step explanation:
solve the first for y and substitute in the second:
y = 15-x
x(15-x) = 15
15x - x� = 15
15x - x� - 15 = 0
-x� + 15x - 15 = 0
x� - 15x + 15 = 0
Answer:
P = 0.05
Step-by-step explanation:
12 months * 30 days each = 360 days
From 306 days, we have to select 8 days = 360C8 ways(Total ways)
We want each days from different month. First, we have to select 8 month from 12 month = 12C8 ways
---By selecting 8 month, we will select a days from each month. That can be done in = 30C1 * 30C1 * .................30C1 (8 ways) [From a month with 30 days, we can select a day in 30C1 ways = 30 ways]
Therefore P = Number of ways of selecting each days from different month / Total number of ways
P = 12C8 * 30^8 / 360C8
P = 495 * 656100000000 / 6469697679132645
P = 0.0501985588982791
P = 0.05
Hence the probability that each day is from a different month is 0.05
5x² + |x+1| > 0
5x² + x + 1 > 0
x+1 > 0 because it came from absolute
5x² > 0 because it’s squared
When you try a number you should put it in the original equality
5x² + |x+1|
