whiteBearr
contestada

The distance covered by the car is x² + 2x - 15 kilometers at (x - 3) hours. Find the Speed of the car.



The length of a paper is 4 units longer than its width. If the Area of the paper is 77 square units, what is the measure of the length of the paper?



Helpp plss ​

Respuesta :

  • Distance=x^2+2x-15
  • Time=(x-3)h

Speed=Distance/Time

[tex]\\ \tt\longmapsto Speed=\dfrac{x^2+2x-15}{x-3}[/tex]

[tex]\\ \tt\longmapsto Speed=(x+5)km/h[/tex]

#2

  • W be x
  • L be x+4

AtQ

[tex]\\ \tt\longmapsto x(x+4)=77[/tex]

[tex]\\ \tt\longmapsto x^2+4x=77[/tex]

[tex]\\ \tt\longmapsto x^2+4x-77=0[/tex]

[tex]\\ \tt\longmapsto x^2+11x-7x-77=0[/tex]

[tex]\\ \tt\longmapsto x(x+11)-7(x+11)=0[/tex]

[tex]\\ \tt\longmapsto x-7(x+11)=0[/tex]

  • Take it positive

[tex]\\ \tt\longmapsto x=7[/tex]

  • L=x+4=7+4=11units