Question

can anyone plz tell me however to find value of X in the following

Answer 1

by cross multiplication method

5×21=-7×x

x=105/-7

x=-15

Answer 2

Hey friend here is your answer:

a)We cross-multiply so,
   5(21)=-7(x)
  105=-7x
  105/7=x
  15=x

b)We cross multiply so,
   -14(4)=-7(x)
   -56=-7x
   -56/-7[minus,minus cancel]
   8=x

c)We cross multiply so,
  33(x)=-9(11)
  33x=-99
  x=-99/33
  x=-3

Hope this helps