Question

in the given figure a b parallel DC find the value of x

Answer 1

triangle AOB ≅ triangle DOC

AO/CO=BO/DO

3x-19/x-5=x-3/3 --->X

by cross multiplication,

3(3x-19)=(x-5)(x-3)

9x-57=x^2-8x+15

x^2-17x+72=0 --------> A)

by using factorization,

x^2-9x-8x+72=0

x(x-9)-8(x-9)=0

x-9=0, x-8=0

x=9, x=8

value of x is 9 & 8