Answer:
a₁ = - 24
Step-by-step explanation:
The n th term of an AP is
= a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Given a₇ = 2a₅ , then
a₁ + 6d = 2(a₁ + 4d) = 2a₁ + 8d ( subtract 2a₁ + 8d from both sides )
- a₁ - 2d = 0 → (1)
The sum to n terms of an AP is
=
[ 2a₁ + (n - 1)d ]
Given
= 84 , then
(2a₁ + 6d) = 84
3.5(2a₁ + 6d) = 84 ( divide both sides by 3.5 )
2a₁ + 6d = 24 → (2)
Thus we have 2 equations
- a₁ - 2d = 0 → (1)
2a₁ + 6d = 24 → (2)
Multiplying (1) by 3 and adding to (2) will eliminate d
- 3a₁ - 6d = 0 → (3)
Add (2) and (3) term by term to eliminate d
- a₁ = 24 ( multiply both sides by - 1 )
a₁ = - 24
Answer:
a*sqrt(x+b) + c = d
or
a*√(x+b) + c = d
Step-by-step explanation:
Answer: A) -9
Step-by-step explanation:
If x = -2
Then
= 
So, it is -9
1,2,4 & 8
12*2<span> = 24</span>
32*2<span> = 64 </span>
44*2<span> = 88 </span>
6*4 = 24
16*4 = 24
<span>etc. </span>
6w-y=2z
6w=2z+y
w=(2z+y):6
w=(z:3)+(y:6)