Explanation:
1. ∠BAC≅∠BCA, ∠ABD≅∠ADB; Reason: definition of isosceles triangles
2. ∠ABD +∠BAC +∠ADB = 180°; Reason: sum of internal angles is 180°
3. ∠BAC = 180° -2(∠ABD) = 36°; Reason: Subtraction and substitution properties of equality
4. ∠BAC +∠BCA +∠ABC = 180°; Reason: sum of internal angles is 180°
5. ∠BCA = 180° -2(∠BAC) = 108°; Reason: Subtraction and substitution properties of equality
6. ∠ABD +∠DBC = ∠ABC; Reason: Angle sum theorem
7. ∠DBC = ∠ABC -∠ABD = 108° -72° = 36°; Reason: Subtraction and substitution properties of equality
8. ∠BCA = ∠BAC = 36°; Reason: Substitution property of congruence
9. ΔBCD is isosceles; Reason: Base angles DBC and BCA are congruent.
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There may be extra steps involved if you separately use subtraction and substitution properties of equality, or if you separately claim congruence of angles and equality of their measures. We have assumed that the definition of "isosceles triangle" includes the fact of equal side lengths <u>and</u> equal base angles.
Answer: okay
Step-by-step explanation:
The equation is:
13.25h = 278.25
Solve for h in this case by dividing 278.25 by the 13.25 dollars per hour.
The answer will be:
21 hours
300.75 you need to find the length, width, and height. then multiple everything together and then by 2
Lets us start with finding the inner angles of the triangle. The bottom right angle shall be 70 degrees as it is opposite. The 100 degrees shall add together to make 200. 360-200 = 160. 160 / 2 = 80. So, Now we know bottom left angle (80) and bottom right (70). 80 + 70 = 150. In a triangle, angles add to 180 so 180 - 150 = 30. 30 = 2x which means that x = 15
15
