Answer:
S₁₅ = 645
Step-by-step explanation:
The sum to n terms of an arithmetic sequence is
= 
[ 2a₁ + (n - 1)d ]
where a₁ is the first term and d the common difference
Using the nth term formula 
= 5n + 3 , then
a₁ = 5(1) + 3 = 5 + 3 = 8
a₂ = 5(2) + 3 = 10 + 3 = 13 , then
d = a₂ - a₁ = 13 - 8 = 5
Thus
S₁₅ = 
[ (2 × 8) + (14 × 5) ]
= 7.5( 16 + 70)
= 7.5 × 86
= 645
In order to prove this, you simply plug in the number 2 everywhere you see X:
4^(2) = 8(2).
Simplify
16 = 16 √
Since this checks out, x is proven to be 2.
Answer:
17
Step-by-step explanation:
Let the larger number be represented by x
Let the smaller number be represented by y
from the question, the next equations can be gotten :
x - y = 9 equation 1
x = 1 + 2y equation 2
Substitute for x in equation 1
1 + 2y - y = 9
1 + y = 9
Collect like terms
y = 9 - 1
y = 8
Substitute for y in equation 1 and solve for x (the larger number)
x - 8 = 9
x = 9 + 8
x = 17
481,000
this is the answer because standered form is just asking to write the number out instead of notation
Answer:
78
Step-by-step explanation:
Use PEMDAS for questions like these (Parenthesis, Exponents, Multiplication, Division, Addition, Subtraction) It gives an order in which you should solve the problem. In this case, put 46 instead of T to get (46*2)-14. If we look at PEMDAS, it shows that we need to do what is in the parenthesis first. So, 46x2=92. You get 92-14. Solve that and you get 78
