Quadratic equation

Determine the numbers b, c that the numbers x1 = -7 and x2 = -4 were roots of quadratic equation:

-5x **2 + b x + c = 0 $    $

Result

b =  -55
c =  -140

Solution:

Solution in text c =







Leave us a comment of example and its solution (i.e. if it is still somewhat unclear...):

Showing 0 comments:
1st comment
Be the first to comment!
avatar




To solve this example are needed these knowledge from mathematics:

Looking for help with calculating roots of a quadratic equation?

Next similar examples:

  1. Roots
    parabola Determine the quadratic equation absolute coefficient q, that the equation has a real double root and the root x calculate: ?
  2. Variations 4/2
    pantagram_1 Determine the number of items when the count of variations of fourth class without repeating is 552 times larger than the count of variations of second class without repetition.
  3. Equation
    calculator_2 Equation ? has one root x1 = 10. Determine the coefficient b and the second root x2.
  4. Discriminant
    Quadratic_equation_discriminant Determine the discriminant of the equation: ?
  5. Product
    floring The product of two consecutive odd numbers is 899. What are this numbers?
  6. Combinations
    math_2 From how many elements we can create 990 combinations 2nd class without repeating?
  7. Quadratic equation
    parabola_1 Solve quadratic equation: x2+16x-225=0
  8. Quadratic function 2
    parabola1 Which of the points belong function f:y= 2x2- 3x + 1 : A(-2, 15) B (3,10) C (1,4)
  9. AP - simple
    sigma_1 Determine the first nine elements of sequence if a10 = -1 and d = 4
  10. Reciprocal
    complex_numbers Calculate reciprocal of z=-0.6+1.6i:
  11. Average
    chart If the average(arithmetic mean) of three numbers x,y,z is 50. What is the average of there numbers (3x +10), (3y +10), (3z+10) ?
  12. PIN - codes
    pin How many five-digit PIN - code can we create using the even numbers?
  13. Theorem prove
    thales_1 We want to prove the sentense: If the natural number n is divisible by six, then n is divisible by three. From what assumption we started?
  14. Confectionery
    cukrovinky The village markets have 8 kinds of sweets, one weighs 15 grams. How many different ways a customer can buy 0.915 kg sweets.
  15. Sequence 2
    seq2 Write the first 4 members of an arithmetic sequence a5=-18, d=-7
  16. Reference angle
    anglemeter Find the reference angle of each angle:
  17. Trigonometry
    sinus Is true equality? ?