Comment
There are 4 terms in this series
That's because the summation (Sigma) goes from 3 to 6 inclusive. So k takes on values of 3,4,5,6
You could use this summation formula
Formula
Sum = (a + L)n/2
Substitution
a is the first term.
k = 3 for the first term
a = -5k + 20
a = -5(3) + 20
a = -15 + 20
a = 5
For the last term k = 6
L = -5(6) + 20
L = -30 + 20
L = - 10
Sum
Sum = (5 - 10)*4/2
Sum = -5 * 2
Sum = -10
Comment
You may wonder how come the last term and the sum are the same. The reason to be found by figuring out the 4 terms and adding them together.
When k = 3, -5k + 20 = -15 + 20 = 5
When k = 4, -5k + 20 = -20 + 20 = 0
When k = 5, -5k + 20 = -25 + 20 = -5
When k = 6, -5k + 20 = -30 + 20 = -10
Sum = 5 + 0 - 5 - 10 = - 10
Conclusion.
It is an accident of the numbers.
Answer: - 10 = the Sum
Eighteen times twelve is 216... if that's what you're asking...
Answer:
Below
Step-by-step explanation:
The corners are the vertices of the rectangle
So to Kick the ball from the corner to the opposite one the player must kick far enough to cross all the width.
The width is 54 m
Then the distance needed is 54 m at least if the ball goes straight.
1/4 exact form, 0.25 decimal form.
The answer is B) x=5
Have a great day/night :)