Step-by-step explanation:
3x² + 22x + 35 = 0
(3x + 7)(x + 5) = 0
3x + 7 = 0
x = -7/3
or x+5 = 0
x = -5
Answer:
4
Step-by-step explanation:
4+3a=16
-4. -4
3a=12
/3. /3
a=4
Answer: Choice A
S9 = (9/2)*(2+26)
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The formula is
Sn = (n/2)*(a1+an)
where
Sn = sum of the first n terms (nth partial sum)
n = number of terms
a1 = first term
an = nth term
In this case,
n = 9
a1 = 2 (plug in n = 1 into the formula an = 3n-1 and simplify)
an = a9 = 26 (plug n = 9 into the formula an = 3n-1 and simplify)
So,
Sn = (n/2)*(a1+an)
S9 = (9/2)*(2+26)
will help us find the sum of the first 9 terms of this arithmetic sequence
Answer:
x = 9º
∠B = 40º
Step-by-step explanation:
5x-5º = 3x+13º
<em>[add 5 to both sides]</em>
5x = 3x+18º
<em>[subtract 3x from both sides]</em>
2x = 18º
<em>[divide each side by 2]</em>
x = 9º
/ / / / / / / / / / / / / / / / / / /
3x+13º = 3(9º)+13º=27º+13º = 40º
