Find missing angles (straight line, corner, crossing lines)

Answer Key - Grade 7 Math Worksheet - Building Confidence

Circle the best answer, or write your answer on the line.

1. 1.

   Bo props the classroom door open for a breeze, and one curious bee flies in. The door makes a 122° angle with the straight wall. What is angle x on the other side, in degrees?

   58
2. 2.

   Esme tilts a desk lamp so its arm leans 35° from the flat desk, aimed right at some very messy notes. What is angle x on the other side of the arm, in degrees?

   145
3. 3.

   Kira sews a straight stitch line out from the square corner of a quilt patch. One part of the corner is 27°. What is the other part, angle x, in degrees?

   63
4. 4.

   Luz draws a line from the square corner of a sheet of paper for a fold-it-yourself project. One part of the corner is 58°. What is the other part, angle x, in degrees?

   32
5. 5.

   Milo hangs a string of paper stars from the square corner of the window frame. One part of the corner is 33°. What is the other part, angle x, in degrees?

   57
6. 6.

   Ren ties two straight kite sticks so they cross. One angle between the sticks is 103°. What is angle x, next to it on the same stick, in degrees?

   77
7. 7.

   On Tala's town map, two straight streets cross by the library. One angle at the crossing is 64°. What is angle x, next to it along the same street, in degrees?

   116
8. 8.

   Zee leans one pencil against another pencil lying flat on the desk, like a tiny ramp. The angles on each side are 125° and x. What kind of angle pair are they?

   • Complementary angles: they add to 90°, like a square corner
   • Supplementary angles: they add to 180°
   • Vertical angles: they are equal
9. 9.

   Ari lays a ribbon out from the square corner of the party table. The ribbon splits the corner into a 36° angle and angle x. What kind of angle pair are they?

   • Supplementary angles: they add to 180°
   • Complementary angles: they add to 90°
   • Vertical angles: they are equal
10. 10.

    Jun's bike stands on its kickstand on flat ground. The kickstand makes a 57° angle with the ground, and angle x is on the other side. Which equation finds x?

    • x + 57 = 180
    • x + 57 = 360
    • x + 57 = 90
    • x = 57