The common difference, d, can be determined by subtracting the two consecutive values:
1 - 5 = -4
-3 - 1 = -4
-7 - -3 = -4
Then, using the equation:
an = a1+ d(n-1)
a_21 = 5 + (-4)(21 - 1)
a_21 = -75
The answer is letter D. I hope I was able to help you. Have a good day!
Answer:
7/12
Step-by-step explanation:
Answer: f(x)= -x
Step-by-step explanation:
-x is a reflection of x and I used my graphing calculator and it checks out
Answer:
A = -9, B = 65
Step-by-step explanation:
Take the square root of both sides of the equation:
h + 9 = ±√65
Subtract 9 from both sides of the equation:
h = -9 ± √65
Comparing this to the form
h = A ± √B
we see that A = -9 and B = 65.
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A lot of math is about matching patterns of numbers and variables. Here, you're asked to match the expression -9±√65 to the pattern A±√B and identify the values for A and B that make these expressions identical.
It should not be difficult to see that the stuff on the left side of ± is the value of A. That stuff is -9.
The stuff under the radical is the value of B. That stuff is 65.
