elitedeltaproduction elitedeltaproduction
  • 01-12-2018
  • Mathematics
contestada

If -5 is a root of the quadratic equation 2x^2+px+15=0 and the equation p(x^2+x) +k=0 has equal rootsv then find p and k

Respuesta :

remotecontrolbrain
remotecontrolbrain remotecontrolbrain
  • 01-12-2018

Answer:

p=13, k = 3.25

Step-by-step explanation:

First, determine p:

[tex]2x^2+px+15=0\\x=-5:\\2(-5)^2+p(-5)+15=0\\-5p+65=0\\\implies p=13[/tex]

Use this value in the second equation

[tex]13(x^2+x)+k=0[/tex]

and write the condition for that equation having equal roots, i.e., its determinant must equal 0:

[tex]13x^2+13x+k=0\\D=b^2-4ac=13^2-4\cdot13\cdot k=0\\52k=169\implies k = 3.25[/tex]


Answer Link

Otras preguntas

how is aluminium foil able to reduce heat loss through the walls of a house
A bottle of fruit juice is 800 milliliters. How many liters of fruit juice are in 120 bottles?
why did farmers follow railroads into the texas frontier
How to make a mixed fraction
What is x^2+8x-5 in vertex form? Please explain.
which of the following did not trigger Haiti's fight for independence
Read the following idioms and figurative definitions. Match the definitions to its corresponding idiom. Remember, you are looking for what these idioms really m
PLEASE CHECK MY ANSWERS (PART 2)
Simplify. 26 + (–3) ∙ (–8) A. –184 B. –2 C. 2 D. 50
por que os vulcões e os terremotos são mais freqüentes em certas regiões do planeta