Step-by-step explanation:
t8 = a1 + (n - 1)*d
t8 = 17
17 = a1 + 7*d
t12 = 25
25 = a1 + 11d
17 = a1 + 7d Subtract
8 = 4d Divide by 4
8/4 = 4d/4
2 = d
17 = a1 + 7d
17 = a1 + 7*2
17 = a1 + 14 Subtract 14
3 = a1
Sum 20 terms
The 20 term = a1 + 19*2
The 20 term = 3 + 38
= 41
Sum = (a1 + a20) * 20 / 2
Sum = (3 + 41)* 20/2
Sum = 44 * 10
Sum = 440
Answer:
B
Step-by-step explanation:
9x - 12 = 36
9x = 36 + 12
9x = 48
9x = 48 matches B, and doesn't match the others
3x = 2x ( alternate exterior angel)
3x - 2x = 0
x = 0
The correct answer is true because the origin will always be (0,0)
