Me

which expression represents the value of x?

Step-by-step explanation:

By the Pythagorean theorem, triangle BCD has

and triangle ABD has

.

Substituting the first equation into the second equation for gives the equation

Now triangle ABC has

Expanding out the left side, .

Now substitute the equation from before, , into the new equation.

We work to isolate by adding to both sides of equation and subtracting from both sides.

Divide both sides by 2 and you get

Assume that x is positive and square root both sides to get the final result of

c.)

step-by-step explanation: