Answer:
Smallest angle = 40
Step-by-step explanation:
Angle sum property:Sum of all three angles of triangle is 180
2x - 6 + 3x + 5 + 2x + 20 = 180 {Combine like terms}
2x + 3x + 2x - 6 + 5 + 20 = 180
7x + 19 = 180 {Subtract 19 from both sides}
7x = 180 - 19
7x = 161 {Divide both sides by 7}
x = 161/7
x = 23
2x - 6 = 2*23 - 6 = 46 - 6 = 40
3x + 5 = 3*23 + 5 = 69 + 5 = 74
2x + 20 = 2*23 + 20 = 46 + 20 = 66
Smallest angle = 40
Answer:
30 books
Step-by-step explanation:
bookshelf is 45 inches
each book is 1 1/2 inches
45 / 1 1/2 = 30
30 books can fit on the shelf
By the Pythagorean theorem, the missing side is -sqrt7. The definition of sin is side opposite over hypotenuse, so go into Q2 and make an angle and label the side opposite the angle with a 3 and the hypotenuse a 4. The other leg is -sqrt7 cuz x is negative in Q2. The cosine of an angle is the side adjacent over the hypotenuse, so the cos then is -sqrt7/4