Use rounding or compatible numbers to estimate the sum

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

Which point on the x-axis lies on the line that passes through point c and is parallel to lino ab?

Can someone factor this fully? my friend and i have two different answers and i would like to know if either of them is right. you in advance. a^2 - b^2 + 25 + 10a