Question

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

Answer 1

• Distance=x^2+2x-15
• Time=(x-3)h

Speed=Distance/Time

$\\ \tt\longmapsto Speed=\dfrac{x^2+2x-15}{x-3}$

$\\ \tt\longmapsto Speed=(x+5)km/h$

#2

• W be x
• L be x+4

AtQ

$\\ \tt\longmapsto x(x+4)=77$

$\\ \tt\longmapsto x^2+4x=77$

$\\ \tt\longmapsto x^2+4x-77=0$

$\\ \tt\longmapsto x^2+11x-7x-77=0$

$\\ \tt\longmapsto x(x+11)-7(x+11)=0$

$\\ \tt\longmapsto x-7(x+11)=0$

• Take it positive

$\\ \tt\longmapsto x=7$

• L=x+4=7+4=11units