Answer:
10 friends
Step-by-step explanation:
we know that
The formula of the sum is equal to
![sum=\frac{n}{2}[2a1+(n-1)d]](https://tex.z-dn.net/?f=sum%3D%5Cfrac%7Bn%7D%7B2%7D%5B2a1%2B%28n-1%29d%5D)
where
a1 is the first term
n is the number of terms (number of friends)
d is the common difference in the arithmetic sequence
In this problem we have


----> the common difference
substitute in the formula and solve for n
![275=\frac{n}{2}[2(5)+(n-1)(5)]](https://tex.z-dn.net/?f=275%3D%5Cfrac%7Bn%7D%7B2%7D%5B2%285%29%2B%28n-1%29%285%29%5D)
![550=n[10+5n-5]\\ \\550=10n+5n^{2} -5n\\ \\5n^{2}+5n-550=0](https://tex.z-dn.net/?f=550%3Dn%5B10%2B5n-5%5D%5C%5C%20%5C%5C550%3D10n%2B5n%5E%7B2%7D%20-5n%5C%5C%20%5C%5C5n%5E%7B2%7D%2B5n-550%3D0)
Solve the quadratic equation by graphing
The solution is n=10
see the attached figure
therefore
She had 10 friends who got stickers
The correct answer is option D.
Explanation:
Inverse variation implies negative relationship. This means that as one of the quanties being compared increases the other decreases and vice versa..
Answer:Explanation: The formula for the equation of a circle is (x – h)2+ (y – k)2 = r2, where (h, k) represents the coordinates of the center of the circle, and r represents the radius of the circle. If a circle is tangent to the x-axis at (3,0), this means it touches the x-axis at that point.
Step-by-step explanation: