Its is equal to 21 because 3x3 is 9 42/7 is 6 then 6+6=12 so then 9 +12=21
First of all, you have to manipulate the equation into the standard

form. You can simplify the 1's on both sides and you have

This means that your coefficients are

And since the solving formula is

Plugging your values yields

Answer:
Simplifying
8x + -4y = 24
Solving
8x + -4y = 24
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '4y' to each side of the equation.
8x + -4y + 4y = 24 + 4y
Combine like terms: -4y + 4y = 0
8x + 0 = 24 + 4y
8x = 24 + 4y
Divide each side by '8'.
x = 3 + 0.5y
Simplifying
x = 3 + 0.5y
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The resulting equation if Becca isolated x² in the first equation and then substituted it into the second equation is (9-y²) / 25 - y²/36 = 1
<h3>Equation</h3>
x² + y² = 9
x²/25 - y²/36 = 1
From (1)
x² = 9 - y²
substitute x² = 9 - y² into (2)
x²/25 - y²/36 = 1
(9-y²) / 25 - y²/36 = 1
Therefore, the resulting equation is option C; (9-y²) / 25 - y²/36 = 1
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Answer:
B
Step-by-step explanation: