Answer: x= 1, 
Step-by-step explanation:
The quadratic equation is
and
So we just need to sub in the proper numbers from the equation given, in this case, it would result in
and
Once we get this we can either manually simplify or use a calculator, using a calculator would result in the answers
x= 1,
I'm confused too and I'm supposed to be an expert. I'm not entirely sure what frequency density is. We'll just treat this as a histogram.
Let's assume each five minute interval gives a value equal to or proportional to the number of people that finished in that interval.
From 0 to 50 we have 10 intervals; let's just make this into a table
0-5 0
5-10 40
10-15 40
15-20 30
20-25 30
25-30 25
30-35 25
35-40 25
40-45 25
45-50 15
From 0 to 40 that adds up to
0+40+40+30+30+25+25+25 = 215
From 0 to 50 that's
215+25+15 = 255
The fraction less than 40 is 215/255 = 43/51 ≈ .843
Answer: 84.3%
7 inches → 280 yards
1 inch → 280 ÷ 7 = 40 yards
5 inches → 40 x 5 = 200 yards
Area = 280 x 200 = 56 000 yards
Answer: 56 000 yards
Evaluate question answers
1. 6x7 -3
V
42 - 3
V
39
Answer
39
2. 2x6+3x7 - (-3)
V
12 + 21 - (-3)
V
12 + 21 + 3
V
36
Answer
36
3. 5 x (-3) +7 - 6
V
-5 x3+7 - 6
V
-15 + 7- 6
V
-14
Find the sum or difference answers
1. Simplify or expand
(16m 4 - 8m + 3) + (-7m4 - m2 - 8)
16m4 - 8m + 3 - 7m4 - m2 - 8
V
9m4 - 8m - 5 - m2
V
9m 4 - m2 - 8m - 5
Answer
9m 4 - m2 - 8m - 5
2. Simplify or expand
(3x2 - 5x + 9) + (2x2 + 9x -4)+ (7x- 11)
v
3x2 - 5x + 9+ 2x2+9x - 4+7x-11
V
5x2 + 11x - 6
Answer
5x2 + 11x - 6
3. Simplify or expand
(3y2 - y - 6) - (42 + 5y+ 3)
V
3y2 - y - 6 - 4y2 - 5y - 3
V
-y2 - 6y - 9
Answer
-y2 - 6y - 9
4. -7 -2+2x2+ 9x
2 Simplify or expand
-7 - 2+2x2+9x
V
-9 + 2x2 + 9x
V
2x2 + 9x - 9
Answer
2x2 + 9x - 9
