Answer:
you add up all of the items and then divide by the total number of items.
Step-by-step explanation:
For example,
Total/Number of Items = Average
Set: 1,6,4,5
(1+6+4+5)/4
16/4 = 4
4 is the average of the items above.
Good luck!!
Answer:
<em>x = 1 + ( √ 10 )/ 2, or x = 1 - ( √ 10 )/ 2; Option A</em>
Step-by-step explanation:
See steps below;
I would prefer answering this question by completing the square, rather than applying a quadratic formula;
3x^2 - 6x - 12 = 0, ⇒ Add 12 to either side,
3x^2 - 6x = 12, ⇒ Divide either side by 3,
x^2 - 2x = 4, ⇒ Write the equation in the form x^2 + 2ax + a^2 = (x + a)^2,
x^2 - 2ax + a^2 = 4 + a^2, ⇒ Solve for a
2ax = -2x,
a = - 1, ⇒ Substitute value of a,
x^2 - 2x + 1 = 4 + 1,
( x - 1 )^2 = 5, ⇒ Solve for x,
x = √5 + 1, and x = - √5 + 1,
In other words; <em>Solution : x = 1 + ( √ 10 )/ 2, or x = 1 - ( √ 10 )/ 2; Option A</em>
