please solve the following algebra problem (solving by substitution

Question

 

Multiple choice

 

Determine the multipliers needed to eliminate the y terms in the system.

 

4x + 9y = 7

3x - 12y = 11

 

a.  Multiply the first equation by 3 and the second by 4.

b.  Multiply the first equation by -3 and the second by 4.

c.  Multiply the first equation by 4 and the second by 3.

d.  Multiply the first equation by 4 and the second by -3.

Answer 1

c. is the answer

4*9y=36y

3*(-12y)=-36y

when you add the equations you would get 36y+(-36y)=0 among other terms...