Answer:
D. There is no mistake.
Step-by-step explanation:
The following lines show the process of factorization by using common factor.
<u>Line 1:</u>
In line 1, the equation is given and is completely fine.

The only thing missing was equate to zero, but the options below talk about correct factors only, therefore this can't be considered as a mistake and can be ignored completely.
<u>Line 2:</u>
In line 2, the terms are grouped, from which we can factor out common terms.

This is also fine.
<u>Line 3:</u>
In line 3, the common term y is taken out from group 1 and 2 from other group.

which is exactly what is given in line 3.
<u>Line 4:</u>
In line 4 the common factors can be seen and easily split into 2 factors.

which is exactly what is given in line 4.
Options:
A. The grouping is correct in line 2. So this option is does not hold.
B. Common factor was factored correctly from group 1. So this option does not hold.
C. Common factor was factored correctly from group 2. So this option does not hold.
D. There is no mistake. This is correct. Thus we choose this option as correct answer.
Answer:
0.72secs
Step-by-step explanation:
Given the height of the ball in air modeled by the equation:
h=−16t²+23t+4
Required
Total time it spent in the air
To get this we need to calculate its time at the maximum height
At the maximum height,
v = dh/dt = 0
-32t + 23 = 0
-32t = -23
t = 23/32
t = 0.72secs
<em>Hence the total time it spend in the air will be 0.72secs</em>
Answer:

Step-by-step explanation:
step 1
Find the slope of the given line
we have

This is the equation of the given line in slope intercept form
The slope is 
step 2
Find the slope of the line parallel to the given line
we know that
If two lines are parallel, then their slopes are the same
therefore
The slope of the line parallel to to the given line is 
step 3
Find the equation of the line in point slope form

we have


substitute

step 4
Convert to slope intercept form

isolate the variable y



Answer:
the area is 10 feet by 10 feet, 100 feet²
subtract the area of the circle from this.
you get it by A = r² * pi
so 5² * 3.14159...
=78.5398163397
100-78.5398163397
is roughly 21.46 square feet