Solve algebraically: y= 6x^2+19x-15 and Y= -12x+15

Question

Y=6X² +19x-15 and Y=-12x=15

Answer 1

The was my mistake.Sorry (deleted)

Answer 2

-12x + 15 = 6x^2 + 19x - 15

 

0 = 6x^2 + 31x - 30

 

0 = (6x  -    5)(x    +    6  )

 

6x - 5 = 0 ---> x = 5/6

 

x + 6  = 0   ---> x = -6

 

check: x = (5/6),

 6(5/6)^2 + 19(5/6) - 15 = 

 6(25/36) + 19(5/6) - 15 =

 25/6 + 95/6 - 90/6 =

 120/6 - 90/6 = 30/6 = 5

 

-12(5/6) + 15 = -60 /6 + 90/6 = 30/6 = 5

 

 

 

check: x = -6,

 

6(-6)^2 + 19(-6) - 15 = 6(36) + 19(-6) - 15 =

  216 - 114 - 15 =

  102 - 15 =

  87

 

-12(-6) + 15 =   72+15 =87