Solving with variables on both sides.

§ 4.4 and 4.5

Review:Watch this short video and do the steps as you watch.

x + 7(x + 1) = 87 8x – 19 = 3x + 31

New:Watch this short video and do the steps as you watch.

3x + 10 = 4x + 5

1. 5y + .6 = -3y – 4.4

Plug your answer back in to check!

2. 1n + 33 = 5 – 1n 6

Now you try it! Do your best.

Watch this short video and do the steps as you watch.

3(x – 1) = 2(x + 7) + 2

Watch this short video and do the steps as you watch. 5 – 2(x + 2) = 3 – (x – 3)

3. -3(a + 14) = 6(2a + 3) 4. 7(8x – 3) + 2x = 72 – 4x

Now you try it!

5. A mountain climber is injured. His partner radios for help, then they begin to descend from their height of 12,500 ft. at a speed of about 200 feet per hour. The rescue team starts at an altitude of 6,500 feet and climbs 1,000 feet per hour.

a. Define the variable. X = hours

Write an equation for when they will meet.

Injured = 12500 – 200x

Rescue = 6500 + 1000x

12500 – 200x = 6500 + 1000x

X = hours

12, 500 – 200x = 6,500 + 1000x

b. How long does it take for them to meet?

c. At what height do they meet?

(Go back and plug in.)

Raul and Tom both with to wrestle at the same weight. Raul, who weighs 148 pounds, plans to gain a pound a week. Tom weighs 166 pounds plans to lose 2 lbs. a week.

a. Define the variable. X = weeks

Write an equation for when they will be the same weight.

R = 148 + 1x and T = 166 – 2x

148 + x = 166 – 2x

148 + x = 166 – 2x

b. How long will it take the boys to reach the same weight?

c. At what common weight will the boys wrestle?

7. 8w < 10w – 30 8. 12x + 3 + 4x 2(7x + 1)

Inequalities: Solve as usual

9. Nine times a number is less than the sum of 5 times that number and 13. Find the number.

9n < 5n + 13

NOTE: “5 times the sum of a number and 13” implies the distributive property.

5(n + 13)

4-4 # 1, 3, 5, 7, 9 4-5 #1, 7, 9, 10, 19, 20

Quiz – Next Tuesday

Homework: