Answer:
The values of r = -3/2 ,7
Step-by-step explanation:
2r2 - 11r - 21 = 0.
The is a quadratic equation in the form
2r²-11r -21= 0
Let's determine the value of r using factorization method
2r² -14r +3r -21= 0.
2r(r-7)+3(r-7)= 0
(2r+3)(r-7)= 0
2r+3= 0
2r= -3
r= -3/2
And
r-7= 0
r= 7
The values of r = -3/2 ,7
