How many strings of eight uppercase english letters are there that start with x, if no letter can be repeated?

As soon as look at the parallelogram abcd shown below: the table below shows the steps to prove that if the quadrilateral abcd is a parallelogram, then its opposite sides are congruent: which choice completes the missing information for reason 5 in the chart? (6 points) congruent parallelograms congruent triangles similar angles similar triangles

Can someone answer this question? : )

What is the measure of ac? 5 units 13 units 26 units 39 units 3x- 2b 6x + 9