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What is the correct evaluation of 3x2 + 4x - 2y2 + 4y + 5, when x is equal to -1 and y is equal to 5?

2 Answers

5 votes

Final answer:

The expression 3x^2 + 4x - 2y^2 + 4y + 5 evaluates to -26 when x = -1 and y = 5.

Step-by-step explanation:

The evaluation of the expression 3x2 + 4x - 2y2 + 4y + 5 when x is equal to -1 and y is equal to 5 is calculated by substituting these values into the equation.

  1. First, substitute x = -1 into 3x2 + 4x, which gives 3(-1)2 + 4(-1) = 3 * 1 - 4 = 3 - 4 = -1.
  2. Next, substitute y = 5 into -2y2 + 4y, which gives -2(5)2 + 4*5 = -2 * 25 + 20 = -50 + 20 = -30.
  3. Add up the results from step 1 and step 2, and include the constant 5 from the original expression to find the final result: -1 - 30 + 5 = -26.

Therefore, the correct evaluation of the expression when x = -1 and y = 5 is -26.

User Piotr Sagalara
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3x2+4(-1)-2(5)2 +4(5)+5=
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6+-4-10+25
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31-14=17
User BassMHL
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8.4k points