The answer to this problem is (x,y) = (-4,2)
Answer:
Help with what
Step-by-step explanation:
So the equation looks like this : 15*3x=78
subtract 15 from both sides: -15 -15
then divide by 3 from both sides
to isolate the variable: 3x=63
3/3x=63/3
x=21 (your mystery number is 21)
1) This is not an arithmetic sequence because it has n².
2) To find 5 first terms of this sequence, you can simply substitute n with 1,2,3,4, and 5, and calculate values of a(1),a(2), a(3), a(4) and a(5).
a(n) = 3n²- 1
n=1 a=3*1² - 1 = 3-1=2
n=2 a=3*2² - 1 = 11
n=3 a=3*3² - 1 =26
n=4 a=3*4² - 1 = 47
n=5 a=3*5² -1 = 74
2,11,26,47,74
Answer C. 2,11,26,47,74.
