Question

find the value of r,if(y+2) is a factor of the polynomial 3y²-4ry-4r²​

Answer 1

Answer:
Values of r are 3 and -1
Step-by-step explanation:
y+2 is a factor of polynomial so,
putting, y+2=0,which gives,y=-2
hence,y=-2 satisfies the polynomial .
So, by putting y=-2 in polynomial ,we will get polynomial=0
( ^ is the symbol of power)
So,3[(-2)^2]-4r(-2)-4[r^2]=0
We get by solving, 3(4)-4r(-2)-4[r^2]=0
12+8r-4[r^2]=0
So, 0=4[r^2]-8r-12
0=4[r^2]-12r+4r-12
0=4r(r-3)+4(r-3)
0=(r-3)(4r+4)
If 0=r-3,then 3=r
If 0=4r+4,then -1=r
Therefore, r can have 2 values
So, r=3,-1