Answer:
Please check the explanation.
Step-by-step explanation:
Given the sequence
2, 6, 10, 14, 18
An arithmetic sequence has a constant difference and is defined as
compute the differences of all the adjacent terms
The difference between all the adjacent terms is the same.
Thus,
and
Therefore, the nth term is computed by:
Thus, position to term rule of 2, 6, 10, 14, 18 multiply by __4___ and subtract by __2__.
5 * 198 = 990
198
* 5
-------
990
Answer:
11. 78
12. 4x² - 3x - 1
Step-by-step explanation:
11. Sum of n whole numbers = ½(n² + n)
Multiply
½*n² + ½*n
= n²/2 + n/2
To find the sum of the first 12 whole number, substitute 12 for n into the equation.
= 12²/2 + 12/2
= 144/2 + 12/2
= 72 + 6
= 78
12. Area of trapezoid = ½(a + b)*h
Where,
a = 5x - 4
b = 3x + 2
h = x + 1
Area = ½(5x - 4 + 3x + 2)*(x + 1)
Area = ½(8x - 2)*(x + 1)
Area = ½[8x(x + 1) -2(x + 1)]
= ½[8x² + 8x - 2x - 2]
Add like terms
= ½(8x² - 6x - 2)
= ½(8x²) - ½(6x) - ½(2)
= 4x² - 3x - 1
Answer:
2x^2+2y^2+4y would be your answer
Step-by-step explanation: