I need help doing angle pairs transversal in 2 step equation there's some examples I need help in 4(2x) (3x - 26)

Evaluate the expression for the given value of the variable 7a - 4a for a =8

Combine like terms to make a simpler expression 3z+z

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