If the sequence is quadratic, then the <em>n</em>-th term (<em>n</em> ≥ 1) is
We're given the first four terms,
Using the formula for the <em>n</em>-th term, this turns into a system of equations,
Solve the system:
• Eliminate <em>c</em> :
(4<em>a</em> + 2<em>b</em> + <em>c</em>) - (<em>a</em> + <em>b</em> + <em>c</em>) = 1 - (-4) ===> 3<em>a</em> + <em>b</em> = 5
(9<em>a</em> + 3<em>b</em> + <em>c</em>) - (<em>a</em> + <em>b</em> + <em>c</em>) = 12 - (-4) ===> 8<em>a</em> + 2<em>b</em> = 16
• Multiply the second equation by 1/2 to get 4<em>a</em> + <em>b</em> = 8, then eliminate <em>b</em> and solve for <em>a</em> :
(4<em>a</em> + <em>b</em>) - (3<em>a</em> + <em>b</em>) = 8 - 5 ===> <em>a</em> = 3
• Solve for <em>b</em> and <em>c</em> :
3<em>a</em> + <em>b</em> = 9 + <em>b</em> = 5 ===> <em>b</em> = -4
<em>a</em> + <em>b</em> + <em>c</em> = 3 - 4 + <em>c</em> = -4 ===> <em>c</em> = -3
Then the rule for the <em>n</em>-th term is
Answer:
exponential
Step-by-step explanation:
The function follows the rule :
- y = 3ˣ
- As y varies directly to the power of the exponent, this function is <u>exponential</u>
If you’re finding X and Y
X=-3 Y=0
Using elimination method
Answer:
72
Step-by-step explanation:
bxh/2
18x8/2=72
Answer:
x + 3y
Step-by-step explanation:
- x + x + x + y x y x y
-x + 2x + 3y
x + 3y