Answer:
Step-by-step explanation:
Find the sum of the first 42 terms of the following series, to the nearest integer.
2,7,12
Solution
The sum is given by
SUM_n=n/2*(a_1+a_n)
a_n=a_1+(n-1)d
a_1=2, n=42, d=5
The 42nd term is therefore given by
a_42=2+(42-1)5=207
SUM_42=42/2*(2+207)=21*209=4389
The sum of the first 42 terms of the series, therefore, is 4389
We can use completing the square.We add 16 and subtract 7 to both sides. Now we get m^2+8m+16=9. The left sides becomes (m+4)^2=9. Taking the square root of both sides and subtracting 4 we get -1 and -7.
Answer:
Slope: 1/4
y-intercept: -6
Step-by-step explanation:
