Answer:
1. 180° ∑triangle angles=180°
2. 2x
3. 52°
Answer:
740
Step-by-step explanation:
The n th term of an arithmetic series is
= a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Given a₃ = 7 and a₇ = (3 × 7) + 2 = 21 + 2 = 23 , then
a₁ + 2d = 7 → (1)
a₁ + 6d = 23 → (2)
Subtract (1) from (2) term by term
4d = 16 ( divide both sides by 4 )
d = 4
Substitute d = 4 into (1)
a₁ + 2(4) = 7
a₁ + 8 = 7 ( subtract 8 from both sides )
a₁ = - 1
The sum to n terms of an arithmetic series is
= 
[ 2a₁ + (n - 1)d ] , thus
= 
[ (2 × - 1) + (19 × 4) ]
= 10(- 2 + 76) = 10 × 74 = 740
Hi Timothy,
1.Which explains why the sequence 216, 12, 2/3 is arithmetic or geometric?
Answer - C.The sequence is geometric because it decreases by a factor of 1/18
The reason I chose C is the fact that the numbers go down greatly, and it has to to be geometric because when you are trying to solve the problem with arithmetic you don't get and exact rule for how to solve the problem.
Answer:
So F=19
Step-by-step explanation:
8=f-(13-2)
8=f-11
+11 +11 You plus 11 by both sides
19=f
You can check you answer by plugging it in
8=19-(13-2)
your answer would still be 19
Yes it is the same. 1/4 +1/4 = 1/2. so 9/10-1/2=9/10-1/2
