Answer:
Step-by-step explanation:
Multiply -1 by -7
-9x^3 + 8x^2 - 7x/6 + 7
First, you need to isolate the x in the first equation.
-x + 5y = 1
Subtract 5y from both sides, leaving you with the following equation:
-x = 1-5y
Because you are trying to solve for positive x and not negative x, you need to make x positive. Therefore you divide both sides by -1. In Algebra, when 1 is the coefficient of the variable, it is not shown, but it is still there. The new equation will be the following: x = 5y-1
Now you just need to substitute the x within the second equation for the x equation we just solved for.
Therefore, the right answer will be 2(5y-1)+4y= -4. Now, all you have to do is choose the answer that states exactly that, which is the first choice.
The 21st term of the given arithmetic sequence is 83. The nth term of an arithmetic sequence is applied to find the required value where n = 21.
<h3>What is the nth term of an arithmetic series?</h3>
The nth term of an arithmetic sequence is calculated by the formula
aₙ = a + (n - 1) · d
Here the first term is 'a' and the common difference is 'd'.
<h3>Calculation:</h3>
The given sequence is an arithmetic sequence.
3, 7, 11, 15, 19, ....
So, the first term in the sequence is a = 3 and the common difference between the terms of the given sequence is d = 7 - 3 = 4.
Thus, the required 21st term in the sequence is
a₂₁ = 3 + (21 - 1) × 4
⇒ a₂₁ = 3 + 20 × 4
⇒ a₂₁ = 3 + 80
∴ a₂₁ = 83
So, the 21st term in the given arithmetic sequence is 83.
Learn more about the arithmetic sequence here:
brainly.com/question/6561461
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