If using the method of completing the square to solve the quadratic equation x2 - 10x - 20 = 0, which number would have to be added to "complete the
square"?

93-8=85

855=17

17*4=68

there are 68 purple marbles in that bag

m∠abd = m∠dbc

step-by-step explanation:

given : ab bisects ∠dbc

as we know that bisection means ab divides   ∠dbc   in two equal angles named as   ∠dba and   ∠abc

so, m∠abd = m∠dbc  

because ab bisects ∠dbc.

hence , the first statement m∠abd = m∠dbc is true.

the answer is  

d.

8 m

hope you got it down chief.