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:
.375
Step-by-step explanation:
divide 3 by 8
28 % is actually written as .28 , so it would be written like this , 600 * 28 = 168.00 = for more simplified form it would be , 168 students , hope this helps
Answer:
2 times x plus 3 times x cubed.
Step-by-step explanation:
2x = 2 * x = two times (multiplied) by x.
+ = plus.
3x^3 = 3 * x^3 = three times (multiplied) by x cubed.
~
The perimeter of a shape is the sum of the lengths of its sides.
So, to find the perimeter of this quadrilateral, all we have to do is add the side lengths and simplify.
(x² - 6) + (2x + 5) + (x² - 3x) + (4x² + 2x)
x² + x² + 4x² + (-3x) + 2x + 2x + (-6) + 5
6x² + (-3x) + 2x + 2x + (-6) + 5
6x² + x + (-6) + 5
6x² + x + (-1)
6x² + x - 1
So, the perimeter of the quadrilateral is the quantity (6x² + x - 1).
Hope this helps!
