First we will find the 11th term
an = a1 + (n-1) * d
a11 = 12 + (11 - 1) * 5
a11 = 12 + 10 * 5
a11 = 12 + 50
a11 = 62
now we use the sum formula...
Sn = (n (a1 + an)) / 2
S11 = (11 (12 + 62)) / 2
S11 = (11 (74)) / 2
S11 = 814/2
S11 = 407
Hey!
Hope this helps...
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Generally what I like to do, to solve questions like this is to substitute the given answers into the equation to solve this faster...
Equation: x^2 + 10x + 12 = 36
A.) (-12)^2 + 10(-12) + 12 = 36
144 - 120 + 12 = 36
24 + 12 = 36
36 = 36
(2)^2 + 10(2) + 12 = 36
4 + 20 + 12 = 36
24 + 12 = 36
36 = 36
Since we found the answer with the first try, we already know the correct answer is A.
So...
The Correct answer is: A.) x=-12 or x=2
Answer:
m∠A = 50°
m∠E = 50°
Step-by-step explanation:
7x - 17 and 2x + 8 are same side exterior angles. They have a sum of 180°.
7x - 17 + 2x + 8 = 180
9x - 9 = 180
9x = 189
x = 21
∠A and 7x - 17 are supplementary. ∠E and 2x + 8 are vertical angles.
m∠A + 7x - 17 = 180
m∠A + 7(21) - 17 = 180
m∠A + 147 - 17 = 180
m∠A + 130 = 180
m∠A = 50
m∠E = 2x + 8
m∠E = 2(21) + 8
m∠E = 42 + 8
m∠E = 50
What are the brackets for? o and im srry for asking but could u mark this "answer" brainliest?? i just need one more to lvl up Im srry ik this isnt an answer but it would mean the world to me if u did
:D
Yasss I think so but I bee help tooo
