Answer:
x = - 7
Step-by-step explanation:
Given
- 2(x + 5) = 4 ← distribute the parenthesis by - 2
- 2x - 10 = 4 ( add 10 to both sides )
- 2x = 14 ( divide both sides by - 2 )
x = - 7
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:
nth term is;
0.5n-0.5
Step-by-step explanation:
As we can see, the first term is 0
The common difference is 0.5-0= 1-0.5 = 1.5-1 = 0.5
Formula for nth term of an arithmetic sequence is;
a + (n-1)d
So we have
0 + (n-1) 0.5
= 0.5n-0.5
Answer:

Step-by-step explanation:
we are given
sequence is geometric
so, we can use nth term formula

we have


we have to find a9
so, we can plug n=9
we get



Answer:
(x - 10)² + (y + 9)² = 20
Step-by-step explanation:
The equation of a circle in standard form is
(x - h)² + (y - k)² = r²
where (h, k) are the coordinates of the centre and r is the radius
The radius is the distance from the centre to a point on the circle
To calculate r use the distance formula
r = √(x₂ - x₁ )² + (y₂ - y₁ )²
with (x₁, y₁ ) = (10, - 9) and (x₂, y₂ ) = (12, - 13)
r = 
=
=
, hence
(x - 10)² + (y - (- 9))² = (
)², that is
(x - 10)² + (y + 9)² = 20