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High school algebra: High school math

HS Algebra: seeing structure, polynomials, rational expressions, creating equations, reasoning with equations (quadratics, systems). A free high school lesson plan, a question set with answers and a printable sheet with its key. Copy it and make it yours.

Lesson plan

Goal

  • Students can do this: hS Algebra: seeing structure, polynomials, rational expressions, creating equations, reasoning with equations (quadratics, systems).

Teach (10 min)

  • Solve a formula for one letter the same way you solve an equation: undo each step, in reverse, on both sides.
  • P = 2l + 2w. Take 2l from both sides: P − 2l = 2w. Divide by 2: w = (P − 2l) ÷ 2.
  • Work one example on the board while students say each step aloud, then do one together.

Practise (15 min)

  • Students work the printable sheet in pairs, then alone.
  • Or practise it as a game with no sign-up: https://peabody.kids/math/lineq.formula?lesson=8-lineq-formula-1&at=8

Exit ticket (5 min)

  • Three questions on a slip:
  • 1. The formula for simple interest is I = prt. Which equation solves it for t?
  • 2. The formula for the area of a rectangle is A = lw. Which equation solves it for l?
  • 3. The formula for simple interest is I = prt. Which equation solves it for t?

Question set

10 questions that read in words, easiest first. Questions that need a picture are on the printable sheet below.

  1. The formula for simple interest is I = prt. Which equation solves it for t?
  2. The formula for the area of a rectangle is A = lw. Which equation solves it for l?
  3. The formula for simple interest is I = prt. Which equation solves it for t?
  4. The formula for distance, rate and time is d = rt. Which equation solves it for t?
  5. The formula for the area of a rectangle is A = lw. Which equation solves it for l?
  6. The formula for the area of a rectangle is A = lw. Which equation solves it for w?
  7. The formula for distance, rate and time is d = rt. Which equation solves it for r?
  8. The formula for distance, rate and time is d = rt. Which equation solves it for t?
  9. The formula for speed that changes steadily is v = u + at. Which equation solves it for u?
  10. The formula for the volume of a box is V = lwh. Which equation solves it for h?
Answers
  1. t = I ÷ (pr)
  2. l = A ÷ w
  3. t = I ÷ (pr)
  4. t = d ÷ r
  5. l = A ÷ w
  6. w = A ÷ l
  7. r = d ÷ t
  8. t = d ÷ r
  9. u = v − at
  10. h = V ÷ (lw)

Printable sheet

Name: ____________________   Date: ____________

High school algebra (High school)

  1. The formula for the area of a rectangle is A = lw. Which equation solves it for w?
  2. The formula for the volume of a box is V = lwh. Which equation solves it for h?
  3. The formula for simple interest is I = prt. Which equation solves it for t?
  4. The formula for simple interest is I = prt. Which equation solves it for t?
  5. The formula for distance, rate and time is d = rt. Which equation solves it for r?
  6. The formula for speed that changes steadily is v = u + at. Which equation solves it for u?
  7. The formula for speed that changes steadily is v = u + at. Which equation solves it for u?
  8. The formula for the volume of a box is V = lwh. Which equation solves it for h?
  9. The formula for the area of a trapezoid is A = ½(a + b)h. Which equation solves it for a?
  10. The formula for the mean of three numbers is m = (a + b + c) ÷ 3. Which equation solves it for c?
  11. The formula for the volume of a box is V = lwh. Which equation solves it for h?
  12. The formula for the area of a trapezoid is A = ½(a + b)h. Which equation solves it for a?
Key
  1. w = A ÷ l
  2. h = V ÷ (lw)
  3. t = I ÷ (pr)
  4. t = I ÷ (pr)
  5. r = d ÷ t
  6. u = v − at
  7. u = v − at
  8. h = V ÷ (lw)
  9. a = 2A ÷ h − b
  10. c = 3m − a − b
  11. h = V ÷ (lw)
  12. a = 2A ÷ h − b

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