Question

will give brainliest also worth 50 points

Answer 1

Answer:

$y = a +( n - 1)d = \\ y = - 20 + 2.5 \times (17 - 1) = - 20 + 2.5 \times 16 = \\ - 20 + 40 = 20 \\ \\ \\ \\ y = - 15 + 4 \times (31 - 1) = \\ - 15 + 4 \times 30 = \\ - 15 + 120 = 105$

Answer 2

Answer:

42.  20

40.  105

Step-by-step explanation:

42.

a_n = a_1 + (n - 1)d

a_1 = -20

d = 2.5

n = 17

a_17 = -20 + (17 - 1)(2.5)

a_17 = -20 + 16(2.5)

a_17 = 20

40.

-15, -11, -7, -3

d = -11 - (-15) = -11 + 15 = 4

a_31 = -15 + (31 - 1)4

a_31 = -15 + 30(4)

a_31 = -15 + 120

a_31 = 105