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Find the x-intercepts of the function g(x)=8x^{2} −10x−3

User Ironv
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1 Answer

7 votes

Answer:
[-(1)/(4), (3)/(2)]

Explanation:

Factor:


  • g(x) = 8x^(2) -10x-3

  • g(x) = x^(2) -10x-24 ---> multiply constant (3) by coefficient of first term

  • g(x) = (x+(2)/(8))(x-(12)/(8) ) ---> factor (multiplies to 24 and adds to -10. Divide factors by 8 since you multiplied by 8 in previous step)

  • g(x) = (x+(1)/(4))(x-(3)/(2)) ---> simplify

  • g(x) = (4x+1)(2x-3) ---> move denominator of fraction to be coefficient of x

Solve:


  • 0 = (4x+1)(2x-3) ---> set equation equal to 0.

  • 0 = 4x + 1 ---> make each parentheses equal to 0.

  • -1 = 4x

  • -(1)/(4) = x ---> x intercept

  • 0 = 2x - 3

  • 3 = 2x

  • (3)/(2) = x ----> x intercept
User Aubrey
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