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

Answer Key - Grade 7 Math Worksheet - Challenge Me

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

1. 1.

   On Jun's trail map, a side path leaves a straight trail. The angles on each side of the path are 52° and (2x + 14)°. What is x?

   57
2. 2.

   Kira draws a line out from the square corner of an envelope for a secret-club stamp. It splits the corner into complementary angles, 28° and (4x + 10)°. What is x?

   13
3. 3.

   Pia's tent poles cross at the top. The (6x + 18)° angle is across from the 138° angle. What is x?

   20
4. 4.

   Three straight streets meet at one point on Tala's town map. Two angles are marked 48° and 73°, as the sketch shows. What is angle x, in degrees?

   59
5. 5.

   Esme draws a line out from the square corner of a poster. It splits the corner into (2x)° and (3x + 5)°. How big is the (3x + 5)° angle, in degrees?

   56
6. 6.

   Jun tapes a paper snowflake chain out from the square corner of a window. It splits the corner into (4x)° and (2x + 6)°. How big is the (2x + 6)° angle, in degrees?

   34
7. 7.

   Two side paths leave a straight trail at one point on Luz's hiking map. Along the trail the angles are 47°, (x + 10)° and 58°. Which equation finds x?

   • x + 10 = 47 + 58
   • 47 + x + 10 + 58 = 360
   • 47 + x + 10 + 58 = 90
   • 47 + x + 10 + 58 = 180
8. 8.

   Noah cuts two lines out from the square corner of a paper square for a pinwheel. They split the corner into 26°, (x + 5)° and 33°. Which equation finds x?

   • 26 + x + 5 + 33 = 180
   • x + 5 = 26 + 33
   • 26 + x + 5 + 33 = 90
   • 26 + x + 5 + 33 = 360
9. 9.

   Pia cuts a cake into four pieces from the center. The angles at the center are 100°, 110°, x° and (2x)°. What is x?

   50
10. 10.

    Bo cuts a sandwich into triangles for a picnic. One triangle has angles of (3x)°, (4x + 5)° and 35°. What is x?

    20