The two angles are the same value. To find, think of the equation 3<em>x</em>+50=6<em>x</em>-10. Put the 6<em>x</em> to the other side of the equation. You shall get -3x+50=-10. Move the 50 to the other side, and you'll end up with -3<em>x</em>=-60. Divide each number by -3 to find <em>x</em> now. Your final answer will be <em>x=20</em>.
Answer: <em>x=20</em>
A+b+c=5982
find the average of the three friends
5982/3=1994
add and subtract one to find the average
1994+1=1995
1994-1=1993
add all the years together to check
1993+1994+1995=5983
You already have the answer. It is "One type of proof is a two-column proof. It contains statements and reasons in columns. Another type is a paragraph proof, in which statements and reasons are written in words. A third type is a flowchart proof, which uses a diagram to show the steps of a proof." which looks correct to me.