3
Work out the size of angle ADE.
Give reasons for your working.

140 degrees

Step-by-step explanation:

Because angle ABC is a right angle (90°), we got an equation: x + 10° = 90°

x + 10° = 90°

x = 90° - 10°

x = 80°

Angle DCB is: 2 x 80° - 20° = 140°

Also angle BAD is a right angle (90°)

Because the total sum of interior angles of a quadrilateral is 360°, that means angle ADC equals: 360° - (90° + 90° + 140°) = 40°

Because ∠ADC + ∠ADE = 180°, angle ADE equals: 180° - 40° = 140°

the equation cos(35) =a/25 can be used to find the length of bc what is the length of bc? round to the nearest tenth

step-by-step explanation:

answer: the proof is mentioned below.

step-by-step explanation:

since, given:   lines bc = ef

prove:   lines ac > ef

          statements                                           reason

1. bc=ef                                           1. given

2. ac= ab+bc                                 2. because b is the point between the  

                                                            line segment ac

3.   ac > bc                                       3. because if a line segment is equal to

                                                          the sum of two line segments then it is

                                                          always greater then each of these

                                                          individual line segments

4. ac > ef                                         4. by equality property.