Answer:
a
Step-by-step explanation:
if you plug 4 in for x it solves it
This is a geometric sequence with common ratio (r) = 2.
an = ar^(n - 1)
a4 = a(2)^(4 - 1) = a(2)^3 = 8a
8a = 80
a = 80/8 = 10
7th term (a7) = 10(2)^(7 - 1) = 10(2^6) = 10(64) = 640
Answer:
1/49
<em>Step by step explanation:</em>
A. Let x = cheese and
y = chocolate
2x + y = 25
x + y = 20
B. Subtract the second equation from the first.
2x + y = 25
-(x + y = 20)
-—————
x = 5
Plug 5 back in to the second equation and solve for y.
x + y = 20
5 + y = 20
Subtract 5 from both sides.
y = 15
5 cheese and 15 chocolate
Used elimination method because coefficients on the y values were both 1 so it was easy to subtract the equations and eliminate the y variable.