Question

The perpendicular bisector of side AB of triangle ABC intersects the extension of side AC at D. Find the measure of angle ABC if measurement of angle CBD=16 degrees and measurement of angle ACB=118 degrees

Answer 1

Answer:

  23°

Step-by-step explanation:

Let the interior angles of ΔABC be referenced by A, B, and C. The definition of point D means that ΔDAB is an isosceles triangle, so we have the relations ...

  A + B + 118 = 180 . . . . interior angles of ΔABC

  A = B +16 . . . . . . . . . . base angles of ΔDAB

Using the expression for A in the second equation to substitute into the first equation, we get ...

  (B+16) +B +118 = 180

  2B + 134 = 180 . . . . . collect terms

  2B = 46 . . . . . . . . . . . subtract 134

  B = 23 . . . . . . . . . . . . divide by 2

m∠ABC = 23°