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Find the value of x. [ (2x-5) (x+4) = 3x + 30]

User Jhpratt
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Final answer:

To solve the equation (2x-5)(x+4) = 3x + 30, we expanded and simplified it to form a quadratic equation, 2x^2 + 3x - 50 = 0. Factoring the quadratic gave us two potential solutions, x = 5 and x = -5, but we disregard the negative solution in context, leaving x = 5 as the final answer.

Step-by-step explanation:

Given the equation (2x-5)(x+4) = 3x + 30, we need to find the value of x. To solve for x, we first expand the left side of the equation:

2x2 + 8x - 5x - 20 = 3x + 30

This simplifies to:

2x2 + 3x - 20 - 3x = 30

Now, we have a quadratic equation of the form ax2 + bx + c = 0:

2x2 = 30 + 20

2x2 - 50 = 0

To find x, we can factor the quadratic equation or use the quadratic formula, x = (-b ± √(b2 - 4ac)) / (2a). However, in this case, factoring will suffice. Thus:

(x - 5)(2x + 10) = 0

Setting each factor equal to zero gives us two possible solutions for x:

  • x - 5 = 0, which gives x = 5
  • 2x + 10 = 0, which gives x = -5.

However, since a negative distance does not make sense in this context, we can disregard the negative solution. Therefore, the solution for x is 5.

User Bsekula
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