Answer:
see explanation
Step-by-step explanation:
the sum to n terms of an arithmetic sequence is
= 
[2a + (n - 1)d ]
where d is the common difference and a is the first term
here d = 9 - 7 = 7 - 5 = 2 and a = 5, hence
= [(2 × 5) + 2(n - 1) ]
= (10 + 2n - 2)
= (2n + 8)
= n² + 4n
When sum = 165, then
n² + 4n = 165 ← rearrange into standard form
n² + 4n - 165 = 0 ← in standard form
(n + 15)(n - 11) = 0 ← in factored form
equate each factor to zero and solve for n
n + 15 = 0 ⇒ n = - 15
n - 11 = 0 ⇒ n = 11
but n > 0 ⇒ n = 11
Answer:
5. Read below
6 . A
Step-by-step explanation:
6. Meaning 8 x 6 = 48
for 5 add the people that ate pasta and chicken.
Subtract that total from 270.
Answer:
Boys :girls!
Step-by-step explanation:
Plz write complete question
Answer:
= 2 1/4 feet
Step-by-step explanation:
Length of chain Jesse needs = 10 1/4 feet
Length of chain Jesse has:
Two small pieces each measuring 2 1/8 feet
= 2 × 2 1/8 feet
= 2 × 17/8
= 34/8 feet
Third piece measuring 3 3/4 feet
Total Length of chain Jesse has = 34/8 feet + 3 3/4 feet
= 34/8 + 15/4
= 34+30/8
= 64/8
= 8 feet
Total Length of chain Jesse has = 8 feet
Length of chain Jesse needs to purchase = Length of chain Jesse needs - Total Length of chain Jesse has
= 10 1/4 feet - 8 feet
= 2 1/4 feet
Length of chain Jesse needs to purchase = 2 1/4 feet
-4x-2y = 16
2y = -4x-16
Get one variable alone on both equations
-4x - 16 = 2y
-4x - 16 = 2y
You'll realize that they're the same equation.
Use substitution
-4x-16 = -4x-16
0 = 0
x = all solutions
Use x = all solutions in an earlier equation to find y
-4x - 16 = 2y
SInce x can be all solutions y is also all solutions
y = all solutions
