Lesson #15- Inequality Word Problems
Keys to Solving Geometric Problems Step 1: Read the problem. What is it asking? Highlight important information. Step 2: Draw and label a diagram. Step 3: Figure out what formulas are required and identify your unknowns. Step 5: Check your work & write a concluding statement. Step 4: Solve the problem showing all work.
pg 86 #13. The length of a rectangular field measures 15 m less than twice the width. If the perimeter measures at least 120 m, determine the minimum width of the field. 2w-15 P ≥ 120 2L + 2w 4w w w ≥ 150 w ≥ 120 2(2w-15) + 2w ≥ 120 6w - 30 ≥ 120 w ≥ 75 m 2 2 Step 1: Find w The minimum width of the field is 75 m. P =2L+2w
15. In a class of at least 30 students, there are 4 more girls than boys. What is the minimum number of girls in the class? x-4: number of boys x 2x x ≥ 34 ≥ 30 + (x – 4) ≥ 30 x ≥ 17 m 2 2 x: number of girls The minimum number of girls in the class is 17. Step 1: Find the # of girls
18. A taxi driver charges an initial fee of $1.25 and then $0.75 per km traveled. In what interval is the distance traveled if the cost of the trip is more than $11 but less than $14.? x ≥ 9.75 > x x > 13 km x: distance travelled (km) 13 < x < 17 is the distance (km) for the trip to cost between $11 and $14. Step 1: Find x for $11 trip x < x x < 17 km Step 2: Find x for $14 trip < 14
Homework pg. 86 # 14,16 &19