Math Problem Statement

Solve problems involving isosceles and equilateral triangles, find missing angle measures, and determine values of x in equations.

Solution

Let's solve these problems step by step.

Triangle problems:

9.

  • Triangle PQR is isosceles.
  • mQ=74m\angle Q = 74^\circ.
  • In an isosceles triangle, two angles are equal, so mP=mRm\angle P = m\angle R.
  • Use the triangle angle sum property: 74+2x=18074 + 2x = 180.
  • Solve for xx (which represents mP=mRm\angle P = m\angle R):
    2x=1062x = 106, x=53x = 53.

10.

  • Triangle EFG has mFEG=106m\angle FEG = 106^\circ.
  • It's a right triangle, so use the triangle angle sum property: 90+106+x=18090 + 106 + x = 180.
  • However, this means xx, mGm\angle G, should not solve this, as one angle already exceeds 90. It's likely an error on the worksheet; otherwise, solve for mE=mG=37m\angle E = m\angle G = 37^\circ.

11.

  • Triangle ABC is an isosceles triangle.
  • mB=mC=48m\angle B = m\angle C = 48^\circ.
  • Find mAm\angle A using the triangle angle sum property: 48+48+x=18048 + 48 + x = 180, x=84x = 84.

12.

  • Triangle NMP is equilateral.
  • All angles are equal, so mM=mN=mP=60m\angle M = m\angle N = m\angle P = 60^\circ.

Value of x Problems:

13.

  • Angle expressions: 8x238x - 23^\circ and 3434^\circ.
  • These angles form a straight line, so they add up to 180180^\circ: 8x23+34=1808x - 23 + 34 = 180 8x+11=1808x + 11 = 180 8x=1698x = 169 x=21.125x = 21.125

14.

  • For an isosceles triangle, set the expressions equal for two base angles or derive the total angle: (9x3)+(9x3)+vertex angle=180(9x - 3) + (9x - 3) + \text{vertex angle} = 180
  • Simplify accordingly and solve for xx.

15.

  • ABCD\triangle ABCD is isosceles with D=E\angle D = \angle E.
  • Equal sides: CD=4x+9CD = 4x + 9, DE=7x5DE = 7x - 5, CE=16x27CE = 16x - 27.
  • Set 4x+9=7x54x + 9 = 7x - 5 to find xx.
  • Once xx is found, plug it back in to find lengths CD,DE,CD, DE, and CECE.

If you need further calculation or explanation on these steps, please let me know!

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Properties of Isosceles Triangles
Properties of Equilateral Triangles
Triangle Angle Sum Property
Solving Linear Equations

Formulas

Sum of angles in a triangle = 180°
Base angles of an isosceles triangle are equal

Theorems

Triangle Angle Sum Theorem
Properties of isosceles and equilateral triangles

Suitable Grade Level

Grades 8-10