REVIEW/WARMUP– DO IN NOTES The three angles of a triangle measure

x, 2x and x-20 degrees. Write and solve an equation for x. What are the three angle measures? (Hint: remember the angles in a triangle sum to 180 degrees).

What is the square of 3/5 written as a fraction? As a decimal? As a percent?

Make sure you have good notes of 1-1 and 2-1 in your binder and with you for class tomorrow.

CHECK HOMEWORK 3. x = 14 4. x = 10.4 5. x = -6 6. c = -3 7. x = -3 8. x = -12 9. x = 2 10. t = 42 11. r = -6 12. R 13. no solution 14. no solution 15. R 16. no solution 17. no solution 18. x > 4 open hole at 4, line to right 19. x > 7/3 open hole at 2.33333.., line to right 20. x ≤ -2 closed hole at -2, line to left Points: completion for each even (up to 9), correct

answer points for #16 and # 20 (up to 2), work points for #6: 1 for writing eqn, one for combining c’s, one for subtracting 5 or 20, and one for dividing by 5 or -5 (up to 4)

Grade = ?/15

WORD PROBLEM EXAMPLES How many cups can you stack on a shelf

that has 14 inches of room under the next shelf if one cup is 3.25 inches tall and each additional cup raises the stack 1 inch?

Step 1 – Write an equation that represents the situation.

Step 2 – Solve the equation

Step 3 – Answer the question!

EXAMPLES How many cups can you stack on a shelf that

has 14 inches of room under the next shelf if one cup is 3.25 inches tall and each additional cup raises the stack 1 inch?

1. 3.25 + 1x ≤ 14(start with a cup 3.25 inches high and add x cups that stack 1 inch each, until the total is up to 14 inches.)2. Subtract 3.25 from both sides, divide by 1 on

both sides (last step is optional, really) - x ≤ 10.75

3. We can’t really stack a fraction of a cup, so the most we can stack is 10 cups plus the first one, for 11 cups total.

EXAMPLES – (LIKE EXAMPLE 1 IN 2-1) Steve Fossett set a speed record for hot

air balloon travel by going 3186.8 miles in 24 hours. Suppose you are trying to break his record. You have so far traveled 1239 miles in 10.5 hours. How fast do you need to travel in the remaining 13.5 hours to beat his record?

Recall: distance = speed x time or speed = d/t

EXAMPLES Steve Fossett set a speed record for hot air balloon

travel by going 3186.8 miles in 24 hours. Suppose you are trying to break his record. You have so far traveled 1239 miles in 10.5 hours. How fast do you need to travel in the remaining 13.5 hours to beat his record?

1. If you’re going to beat him, you need to go farther than 3186.8. So your total distance must be greater than his.

1239 + new distance > 3186.8 Distance = speed * time so new distance equals speed x

* 13.5 hours. 1239 + 13.5x > 3186.8 Solve -> subtract 1239 both sides, divide by 13.5 both

sides X = 144.28 mph ->> he needs to average more than

that speed for the rest of the voyage to break the record!

ASSIGNMENT 2-1 #2,21,40,42-48,53-56 Let’s try #2 together – read the problem

and discuss with partner how to write equation to model it. Write down your equation.