-115
Using the arithmetic formula, your equation appears as so:
an = 15 + (27 - 1) - 5
15 being the first number in the sequence, 27 being the number you're trying to find, and -5 being the common difference.
This will give you the answer of -115.
Hope this helps!
Answer:
20n² - 40n + 20
Step-by-step explanation:
(5n - 5)(4n - 4)
= 5n(4n) + 5n(-4) - 5(4n) - 5(-4)
= 20n² - 20n - 20n + 20
= 20n² - 40n + 20
Another way to do this:
(5n - 5)(4n - 4)
= 5(n - 1) * 4(n - 1)
= 20(n - 1)(n - 1)
= 20(n - 1)²
= 20(n² - 2n + 1)
= 20n² - 40n + 20
Answer:
He burnt 1000 calories per hour when playing basketball.
Step-by-step explanation:
Let B be calories burned playing basketball, and C calories burned canoing.
1800 = B + 2C
3200 = 2B + 3C
From 1st equatipn, we get that B = 1800 - 2C
Replacing into the 2nd equation, we have:
3200 = 2(1800-2C) + 3C
3200 = 3600 - 4C + 3C
3200 = 3600 - 1C
C = 3600 - 3200
C = 400
Knowing C, we find B.
B = 1800 - 2C = 1800 - 2*400 = 1800 - 800 = 1000 calories.
