Question

Find the value of k if x=-2 is a solution of the quadratie equation 2x²+ Kx + 30 = 0.​

Answer 1

Step-by-step explanation:

bhai 2 min

k×3square -10×3=0

9k-30+3=0

9k-27=0

9k=27

k= 27 ÷ 9

k=3

Answer 2

Answer:

19

Step-by-step explanation:

Substituting x=-2

=> 2(-2)²+K(-2)+30=0

=> 8-2K+30=0

=> 2K=38

=> K=38/2= 19

Verification:

Substitute 19 in place of K

=> 2(-2)²+19(-2)+30=0

=> 8-38+30=0

=> 38-38=0

=> 0=0 L.H.S = R.H.S

Therefore K= 19