Missing complementary angle

#complementaryangles#twoanglesaddto90#lesson10

Use the applet to practice finding the value of the missing complementary angle.[br][br]Practice first before you answer the questions [br][br]You can change the value of <DCE (red angle) by moving the red slider. Notice how the angle is named from the points on the lines with the vertex, C, in the middle. [br][br]Find the value of <ECB (green angle) and record your answers.

If <DCE is 75°, what is the measure of <ECB?

If <DCE is 32°, what is the measure of <ECB?

If <DCE is 5°, what is the measure of <ECB?

How do you find the missing complementary angle?

Not sure, I need more practice Subtract the given angle from 90° Add the given angle to 90°

Information: Missing complementary angle