There are 18 terms are in her series
<h3>What is Arithmetic progression series?</h3>
Arithmetic Progression (AP) is a sequence of numbers in order in which the difference of any two consecutive numbers is a constant value.
Given that: t(n) = −9 + 21n=l
a= 12, Sum = 3429
As, Sum of series =3429
n/2 (a+l) =3429
n/2 (12 +21n-9)= 3429
n/2 (3+21n)=3429
21n² + 3n= 6858
21n² + 3n- 6858=0
7n² + n- 2286=0
For solving for n, get
n= 18 or n= -127/7
Thus, there 18 terms in the series.
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40 because 180-60=120 and 120 divided by 3 is 40.
Answer:
c) vertical stretch by a factor of 2
Step-by-step explanation:
Answer:
3 549
Step-by-step explanation:
Answer:
Step-by-step explanation:
a/sina =b/sinb=c/sinc =d=sind
250/sin25 = 459/sinb
250sinb = 459sin25 = 459(0.42261826174) = 193.981782139
sin b = 193.981782139/250 = 0.77592712855
b = sin⁻¹0.77592712855 = 50.88916502