Answer:
4 x (7-x)
Step-by-step explanation:
4 times (multiply) the difference (subtraction) of 7 and a number (seeing as how you don't know that number use a variable, x)
First term = 12
Solution:
A4 = 24
A12 = 56
An = A1 + (n-1)d; this defines the formula of an arithmetic series
A4 = 24 = A1 + (4-1)d
A4 = 24 = A1 + 3d
A12 = 56 = A1 + (12-1)d
A12 = 56 = A1 + 11d
Subtract A4 from A12 to get d (distance)
(56 = A1 + 11d) - (24 = A1 +3d)
32 = 8d
d = 4
Substitute d = 4 into A4
A4 = 24 = A1 + 3(d)
24 = A1 + 3(4)
24 = A1 + 12
24 - 12 = A1
12 = A1
Answer:
42
Step-by-step explanation:
uih
Answer:
-3/2
Step-by-step explanation:
