Answer:

Step-by-step explanation:
To solve this problem you must apply the proccedure shown below:
1. You need to apply the Distributive property on the left member of the equation:

2. Now, you must solve for
, as following:

Answer:A -3,6
Step-by-step explanation: Substitue the answers in and they work out
Answer:
-2n²
Step-by-step explanation:
Using the image attached:
We see that the second differences (blue ones) are all equal so we conclude that this is a quadratic sequence.
The quadratic sequence has the form:

To find the value of a we just divide second difference ( -4 ) by 2:
Now we have:
Substitute
and
into the equation above:
Since
= -2 and
= -8 , after simplification we have:
The solution of this system is:
The general term is :

<h3>
Step-by-step explanation:</h3>
<u>Pythagorus theorum:</u>
9² = 3² + YZ²
81 - 9 = YZ²
√72 = YZ
∴YZ= 8.48 ≈ 8.5
<u>Trigonometry:</u>
We have adjacent as 3, and hypotenuse as 9
cos X = 3/9
X= cos∧-1 (3/9) → <em>[cos inversed]</em>
∴X= 70.5°
We have opposite as 3 and hypotenuse as 9
sin Z= 3/9
Z= sin∧-1 (3/9)→<em> [sin inversed]</em>
∴Z= 19.47 ≈ 19.5