In the diagram AB is parallel to DC.
Angle ABC = 70°
Angle ACD = 55°
Not drawn accurately
Show that triangle ABC is isosceles.
You must give reasons in your working.

Triangle ABC is an isosceles triangle.

Solution:

Given data:

AB is parallel to CD and AC is the transversal.

∠ABC = 70° and ∠ACD = 55°

If two parallel lines are cut by a transversal, then alternate interior angles are congruent.

∠BAC ≅ ∠ACD

m∠BAC = m∠ACD

m∠BAC = 55°

Sum of the angles in a straight line = 180°

m∠ACD + m∠ACB + m∠ABC = 180°

55° + m∠ACB + 70° = 180°

m∠ACB + 125° = 180°

Subtract 125° from both sides, we get

m∠ACB = 55°

In triangle ABC,

∠BAC = 55° and ∠ACB = 55°

∠BAC = ∠ACB

Two angles in the triangle are equal.

Therefor triangle ABC is an isosceles triangle.

8

step-by-step explanation:

to find the amount of gift bags to use all the supplies, find the gcf or greatest common factor. this is the largest number which multiplies evenly into each term.

48 has factors: 1, 2, 3, 4, 6, 8, 12. 16, 24, 48

80 has factors: 1, 2, 4, 5, 8, 10, 16, 20, 40, 80

64 has factors: 1, 2, 4, 8, 8, 16, 32, 64

the highest number factor they all share in common is 8. this means there will be 8 bags with 6 pencils, 10 markers, and 8 stickers in each bag.