Can someone check this?
2x^2 + 50 = −20x
2x^2 + 20x + 50 = 0
2(x^2 + 10x + 25) = 0
2(x + 5)(x + 5) = 0
(x + 5)(x + 5) = 0

x + 5 = 0 or x + 5 = 0
x = − 5, x = − 5
the solution set is
{−5}.

The figure shows triangle def and line segment bc, which is parallel to ef: triangle def has a point b on side de and point c on side df. the line bc is parallel to the line ef. part a: is triangle def similar to triangle dbc? explain using what you know about triangle similarity. part b: which line segment on triangle dbc corresponds to line segment ef? explain your answer. part c: which angle on triangle dbc corresponds to angle f? explain your answer. asap