Home
Class 10
MATHS
Solve the following equatins for x: 8...

Solve the following equatins for x:
`8x^(2)-22x-21=0`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the quadratic equation \(8x^2 - 22x - 21 = 0\), we can follow these steps: ### Step 1: Identify the coefficients The equation is in the standard form \(ax^2 + bx + c = 0\), where: - \(a = 8\) - \(b = -22\) - \(c = -21\) ### Step 2: Factor the quadratic equation We need to factor the quadratic expression. We look for two numbers that multiply to \(a \cdot c = 8 \cdot (-21) = -168\) and add up to \(b = -22\). The two numbers that satisfy these conditions are \(-28\) and \(6\) because: - \(-28 \cdot 6 = -168\) - \(-28 + 6 = -22\) ### Step 3: Rewrite the equation We can rewrite the equation by splitting the middle term: \[ 8x^2 - 28x + 6x - 21 = 0 \] ### Step 4: Group the terms Now, we group the terms: \[ (8x^2 - 28x) + (6x - 21) = 0 \] ### Step 5: Factor by grouping Now we factor out the common terms from each group: \[ 4x(2x - 7) + 3(2x - 7) = 0 \] ### Step 6: Factor out the common binomial We can factor out the common binomial \((2x - 7)\): \[ (4x + 3)(2x - 7) = 0 \] ### Step 7: Set each factor to zero Now we set each factor equal to zero: 1. \(4x + 3 = 0\) 2. \(2x - 7 = 0\) ### Step 8: Solve for \(x\) Now we solve each equation for \(x\): 1. From \(4x + 3 = 0\): \[ 4x = -3 \implies x = -\frac{3}{4} \] 2. From \(2x - 7 = 0\): \[ 2x = 7 \implies x = \frac{7}{2} \] ### Final Solutions The solutions for the equation \(8x^2 - 22x - 21 = 0\) are: \[ x = -\frac{3}{4} \quad \text{and} \quad x = \frac{7}{2} \] ---
Promotional Banner

Topper's Solved these Questions

  • QUADRATIC EQUATIONS

    NAGEEN PRAKASHAN ENGLISH|Exercise Exercise 4b|16 Videos
  • QUADRATIC EQUATIONS

    NAGEEN PRAKASHAN ENGLISH|Exercise Exercise 4c|12 Videos
  • QUADRATIC EQUATIONS

    NAGEEN PRAKASHAN ENGLISH|Exercise Problems From NCERT /exemplar|17 Videos
  • PROBABILITY

    NAGEEN PRAKASHAN ENGLISH|Exercise Revision Exercise Very Short Answer/short Answer Questions|16 Videos
  • REAL NUMBERS

    NAGEEN PRAKASHAN ENGLISH|Exercise Revision Exercise Long Answer Questions|5 Videos

Similar Questions

Explore conceptually related problems

Solve each of the following equatins : 48x^(2)-13x-1=0

Solve the following equations: 2x+5=21

Solve each of the following equatins : 6x^(2)-x-2=0

Solve each of the following equatins : 3x^(2)-243=0

Solve each of the following equatins : 5x^(2)+4x=0

Solve each of the following equatins : x^(2)+12x+35=0

Solve each of the following equatins : 2x^(2)-5x+3=0

Solve each of the following equatins : 9x^(2)+6x+1=0

Solve the following quadratic: \ 8x^2-9x+3=0

Solve each of the following equatins : 6x^(2)+40=31x

NAGEEN PRAKASHAN ENGLISH-QUADRATIC EQUATIONS-Exercise 4a
  1. Solve each of the following equatins : 2x^(2)-5x+3=0

    Text Solution

    |

  2. Solve each of the following equatins : 6x^(2)-x-2=0

    Text Solution

    |

  3. Solve the following equatins for x: 8x^(2)-22x-21=0

    Text Solution

    |

  4. Solve each of the following equatins : 9x^(2)+6x+1=0

    Text Solution

    |

  5. Solve each of the following equatins : 48x^(2)-13x-1=0

    Text Solution

    |

  6. Solve each of the following equatins : 6x^(2)+40=31x

    Text Solution

    |

  7. Factorize sqrt3x^2+11x+6sqrt3

    Text Solution

    |

  8. Solve each of the following equatins : 3sqrt7x^(2)+4x-sqrt7=0

    Text Solution

    |

  9. Solve each of the following equatins : 2sqrt5x^(2)-3x-sqrt5=0

    Text Solution

    |

  10. Solve each of the following equatins : x^(2)+5=(9)/(2)x

    Text Solution

    |

  11. Solve each of the following equatins : x=(3x+1)/(4x)

    Text Solution

    |

  12. Solve each of the following equatins : x+(1)/(x)=2.5

    Text Solution

    |

  13. Solve each of the following equatins : 5x-(35)/(x)=18,xne0

    Text Solution

    |

  14. Solve each of the following equatins : (2)/x^(2)-(5)/(x)+2=0,xne0

    Text Solution

    |

  15. Solve each of the following equations : a^(2)x^(2)+2ax+1=0

    Text Solution

    |

  16. Solve each of the following equatins : x^(2)-(p+q)x+pq=0

    Text Solution

    |

  17. Solve each of the following equatins : a^(2)x^(2)+(a^(2)+b^(2))x+b^(...

    Text Solution

    |

  18. 5. Solve 12abx^2-9a^2x +8b^2x-6ab =0

    Text Solution

    |

  19. Solve each of the following equatins : 4x^(2)-4ax+(a^(2)+b^(2))=0

    Text Solution

    |

  20. Solve each of the following equatins : (x+1)/(x-1)=(3x-7)/(2x-3)

    Text Solution

    |