3 - 2a > 7
We need to solve for a
First, let's subtract 3 on both sides to have the variables on a side and the numbers on another side:
3 - 2a > 7
3 - 2a - 3 > 7 - 3
- 2a > 4
Let's divide both sides by -2 to have a on side and its value on the other side:
-2a > 4
(-2a)/(-2) > (4/-2)
a < -2 (In a case of an inequality, we change the sign when we divide by a negative number to its opposite).
So 3 - 2a > 7 when a < -2 (answer c)
Hope this helps! :D
A1 = first term
a1 = 15
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d = common difference
d = (second term) - (first term)
d = a2 - a1
d = 9-12
d = -3
The negative common difference indicates that the terms are decreasing
Each time we subtract 3, or add -3, to get the next term.
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nth term of arithmetic sequence
an = a1 + d(n-1)
an = 15 + (-3)(n-1)
an = 15- 3n + 3
an = 18 - 3n
Answer is choice D
Answer:
3 :)
Step-by-step explanation:
X² = 18 ; (3√2)² = 3² x 2 = 9 x 2 = 18
