Answer:
The common difference is -5/4
T(n) = T(0) - 5n/4,
where T(0) can be any number. d = -5/4
Assuming T(0) = 0, then first term
T(1) = 0 -5/4 = -5/4
Step-by-step explanation:
T(n) = T(0) + n*d
Let
S1 = T(x) + T(x+1) + T(x+2) + T(x+3) = 4*T(0) + (x + x+1 + x+2 + x+3)d = 240
S2 = T(x+4) + T(x+5) + T(x+6) + T(x+7) = 4*T(0) + (x+5 + x+6 + x+7 + x+8)d = 220
S2 - S1
= 4*T(0) + (x+5 + x+6 + x+7 + x+8)d - (4*T(0) + (x+1 + x+2 + x+3 + x+4)d)
= (5+6+7+8 - 1 -2-3-4)d
= 4(4)d
= 16d
Since S2=220, S1 = 240
220-240 = 16d
d = -20/16 = -5/4
Since T(0) has not been defined, it could be any number.
Answer:
(x-2)/(2x+8)
Step-by-step explanation:
The first step to solve this expression is to use a² - 2a b + b² = (a - b)² to factor the expression
Factor out 2 from the expression
Write 2x as a difference
Factor out x from the expression
Factor out -2 from the expression
Factor out x + 4 from the expression
Reduce the fraction with x - 2
Finally,, distribute 2 through the parenthesis to find your answer
This means that the correct answer to your question is (x-2)/(2x+8)
C
By subtracting 18 to both sides you are separating the 3x because you are not ready to isolate the variable (x) in step 1
-12 and 18
hope this helps :)