Step 1: Group this into two groups:
When you do that, be sure to group the "–" into the group with the 9 and make sure there's "+" between the groups.
Step 2: Factor out the GCF from both individual groups:
Step 3: Notice both groups have that (h+2)? That's a new GCF between the two groups, so factor that out:
Step 4: That 
piece can be factored further, since it's a difference of squares:
Now it's factored.
Let the speed for the first 12 mi be x mi/h, the speed for 18 mi was (x+4) mi/h
thus given that
time=distance/speed
the average time will be:
3=(12+18)/(x+x+4)
3=30/(2x+4)
solving for x we get
3(2x+4)=30
6x+6=30
6x=24
x=4 mi/hr
Answer: 12 mi/hr
Step 2 is wrong and i don't know the other question
Answer:
(x - 3)^2 + (y + 1) = 25
Step-by-step explanation:
First find the midpoint of the diameter, because that represents the center of the circle.
-1 + 7
The x-coordinate of the midpoint is xm = ---------- = 3
2
2 - 4
and the y-coordinate is ym = ---------- = -1
2
And so the center of this circle is at (3, -1).
Use the Pythagorean Theorem to determine the square of the radius:
square of radius = 4^2 + (-3)^2 = 16 + 9 = 25
And so the equation of this circle is (x - 3)^2 + (y + 1) = 25
Answer:
1. 1
2. 8
3. 13
Step-by-step explanation:
hope that helps
