Answer:
its is C because the other ones are obvious wrong. So it has to be C plus i did this test.
Step-by-step explanation:
Answer:
an = a(n-1) - 7
Step-by-step explanation:
the second term is smaller than the first term 7.
a20 = a19 - 7
a19 = a18 - 7
=> a20 = (a18 - 7) - 7
Then you can accumalate until a1
-> a20 = a1 - 19*7 = 86 - 19*7 = -47
The greatest common factor of 40&10 is 10
Answer:
x = 2
Step-by-step explanation:
(x² logₓ27) log₉x = x + 4
Use change of base formula.
x² (log 27 / log x) (log x / log 9) = x + 4
Simplify.
x² (log 27 / log 9) = x + 4
x² (log 3³ / log 3²) = x + 4
x² (3 log 3 / (2 log 3)) = x + 4
x² (3 / 2) = x + 4
3x² = 2x + 8
3x² − 2x − 8 = 0
(x − 2) (3x + 4) = 0
x = 2 or -4/3
Since x > 0, x = 2.
