Four congruent square pieces with side lengths of 6 cm were cut out of corners of a square piece of cardboard

1. find the area of the unshaded square 2. find the area of the large square 3. what is the area of the frame represented by the shaded region show

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

Ntriangle abc, m∠a = 35° and m∠b = 40°, and a=9. which equation should you solve to find b?