Answer:
He needs 7 more consecutive successful first serves to raise his first serve percentage to 60%.
Step-by-step explanation:
After n consecutive serves, his total number of serves is going to be n+8, since he has already served 8 times. In the best case, his number of successful first serves is n+2.
His percentage of succesful first serves is the division of the number of succesful first serves divided by the total number of serves. So

We want
. So







He needs 7 more consecutive successful first serves to raise his first serve percentage to 60%.
Answer:
- reflection in x = 1
- translation up 2
Step-by-step explanation:
The orientation of B is the opposite of the orientation of A, so a reflection is involved. The smallest angle is at the bottom in both figures, and the largest angle is on the right in A and the left in B, so the reflection is left-right, rather than up-down.
The point midway between the largest angle vertices is on the vertical line x=1, so that line can be used for reflection. Reflecting A across that line will put its large-angle vertex at (3, 0), so a translation up 2 units is also needed.
The reflection on x=1 and translation up 2 can be done in either order.
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<em>Additional comment</em>
A combination of reflection and translation is called a "glide reflection." Our choice of x = 1 as the line of reflection takes care of any horizontal translation that would be required if a different vertical line were used. For example, reflection across the y-axis would require a subsequent translation up 2 and right 2.
1. Use the Pythagoras theorem
13^2 = x^2 + 5^2
solve for x and youll get the height of the roof.
2. let x = length of the rpoe)-
x^2 = 9^2 + 12^2
3. Pythagoras again
20^2 = x^2 + 12^2
10x= -8x + 36
-8x -8x
———————-
2x= 36
— —
2 2
X=18