Answer:
1. answer is D
2. Answer is D
3.Answer is B
4. Answer is C
5. Answer is B
6. Answer is D
7.Answer is D
Step-by-step explanation:
Triangle ABC is an isosceles triangle.
Solution:
Given data:
∠ABC = 70° and ∠ACD = 55°
<em>If two parallel lines are cut by a transversal, then alternate interior angles are congruent.</em>
m∠BAC = m∠ACD
m∠BAC = 55°
<em>Sum of the angles in a straight line add up to 180°.</em>
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.
Use Pythagorean theorem to solve.
a^2 + b^2 = c^2
6^2 + b ^2 = 14^2
36 + b^2 = 196
Subtract 36 from both sides.
b^2 = 196-36
b^2 = 160
Take the square root of both sides.
b = sqrt 160
As a decimal
b = 12.649
As a simplified radical
b = 4sqrt10
⓵
-4ỿ = 8
Simplify the left side in order to isolate the ỿ!
-4ỿ = 8
+4 +4
Ỿ = 12
⓶
× + 3y - 3z = -26
Simplify the left side in order to isolate the ×, ỿ and z!
× + 3y - 3z = -26
÷3 ÷3
× + ỿ - 3z = -8,66 periodic
÷-3 ÷-3
× + ỿ + z = 2,88 periodic
⓷
2× - 5ỿ + z = 19
Simplify the left side in order to isolate the ×, ỿ and z!
2× - 5ỿ + z = 19
÷2 ÷2
× - 5ỿ + z = 9,5
÷-5 ÷-5
× + ỿ + z = -1,9
