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Evaluate the expression 8 - 4x * y ^ 2 for x = 3 and y = - 2

1 Answer

4 votes

Answer:

16

Explanation:

8-4x times y^2, x=3 and y=-2

First, plug in both variables. Since x=3, you would substitute 4x in the equation to 4(3). You would do the same to y, but instead it would be in replace of y^2. So it would be -2^2. You now have a new equation:

8-4(3) times -2^2

Next, you start solving the equation. You should follow PEMDAS (Parenthesis, Exponent, Multiplication, Division, Addition, Subtraction). This method is sometimes controversial, but it still works for this problem.

Start by multiplying 4 times 3 which equals 12. Then I solve the exponent. The exponent -2^2 is the same as -2 times -2. The -2 is the number that gets multiplied, and the exponent is how many times -2 gets multiplied times itself. -2 times -2 is 4. You can plug your new numbers back in the equation now.

8-12 times 4

The equation is much easier to solve now. 8-12 is -4. -4 times 4 is 16.

The answer is 16.

User Himanshu Kandpal
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