Ineed find the sum of the first 42 terms of the sequences (12, 16, 20,
a) 3,717
b) 3,948
c) 1,134
d) 4,032

B

Step-by-step explanation:

Note the common difference between consecutive terms of the sequence.

d = 16 - 12 = 20 - 16 = 4

This indicates the sequence is arithmetic with sum to n terms

= [2a₁ + (n - 1)d ]

where a₁ is the first term and d the common difference

Here a₁ = 12 and d = 4, thus

= [ (2 × 12) + (41 × 4) ]

                          = 21( 24 + 164) = 21 × 188 = 3948 → B

b. y = 4x - 2

step-by-step explanation:

to find a parallel equation to an equation, make sure both equations have the same slope but different y-intercepts.

y = 4x + 1

4 = slope

1 = y-intercept

y = 4x - 2

4 = slope

-2 = y-intercept

they both have the same slope but different y-intercepts, so, b. is the correct answer.

and to check your work, you can graph both equations. : )