1 / 8

Expressions, Formulae, and Re-arranging: Learn and Solve Problems!

This chapter teaches how to write expressions and formulas in algebra, substitute values, evaluate equations with powers and roots, and rearrange formulas. It also provides examples and exercises to help students practice these skills and solve problems.

ftaylor
Télécharger la présentation

Expressions, Formulae, and Re-arranging: Learn and Solve Problems!

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 14 Formulae

  2. Learning Objectives • Write expressions in algebra • Write a formula • Know the difference between expressions & formula • Substitute values into formulae and evaluate • Substitute values into formulae with powers & roots • Re-arrange formulae • Solve problems by re-arranging formulae

  3. Writing Expressions & Formulae • An expression does not have an equal sign • A formula does have an equal sign Examples • A box of matches has 55 matches, write an expression for the total matches in n boxes. • Write a formula for the total perimeter, P, of a shape with sides x – 3, x+ 2 & x

  4. Substituting in Formula Examples • What is the value of A in the formula A = pq – r. when p = -1, q = 5 and r = -2 2. Find H when x = 5 and y = 7 in H = 3(3x – 2)

  5. Formulae with Powers & Roots Examples • Find the value of S = (½p)3, when (a) p = 4 (b) p = -4 • Calculate √(5x) when x = 0.4 • Use the formula v = √(u2 + 2as) to find the value of v when a = -9.8, s = 1.67 and u = 45.3

  6. Re-arranging Formulae • Remember that when moving terms to the other side you do the opposite Examples • Make m the subject in k = 8m/5 • Make x the subject in y = 2x + 8 • Make r the subject in A = 3r2 • Make b the subject in T = a + √b

  7. More Re-arranging Examples 5. Make the bold letters the subject in the following: (a) 3a = 4b/5 (b) 3(x – a) = x (c) e = ½mv2 (d) a(b + x) = b(2a – x)

  8. Solving Problems by Re-arranging • The volume of a cuboid, with length 7.8cm and breadth 5cm, is 136.5cm3. Calculate the height of the cuboid. • V = 4/3πr3. Calculate r when the volume is 3.56×104.

More Related