1.1 Variable in Algebra 1.2 Exponents & Powers

A variable expression contains: 1) one or more numbers or variables, and 2) one or more operations. Examples: x n

In expressions, there are many different ways to write multiplication. 1)ab 2)a b 3)a(b) or (a)b 4)(a)(b) 5)a x b We are not going to use the multiplication symbol any more. Why?

Division, on the other hand, is written as: 1) 2) x ÷ 3

Here are some phrases you may have listed. The terms with * are ones that are often used.

Write an algebraic expression for 1) m increased by 5. m + 5 2) 7 times the product of x and t. 7xt or 7(x)(t) or 7 x t

3) 11 less than 4 times a number. 4n ) two more than 6 times a number. 6n + 2 5) the quotient of a number and 12.

Which of the following expressions represents 7 times a number decreased by 13? 1.7x x x x Answer Now

Which one of the following expressions represents 28 less than three times a number? x 2.3x x 4.3x + 28 Answer Now

Write a verbal expression for: 1) 8 + a. The ratio of m to r Do you have a different way of writing these? The sum of 8 and a 2)

Which of the following verbal expressions represents 2x + 9? Answer Now 1.9 increased by twice a number 2.a number increased by nine 3.twice a number decreased by less than twice a number

Which of the following expressions represents the sum of 16 and five times a number? Answer Now 1.5x x x x

base and 3 is called the exponent or power means = 1000 When looking at the expression 10 3, 10 is called the

How is it said? 2 1 Two to the first power2 Two to the second power or two squared 2323 Two to the third power or two cubed 2n 7 Two times n to the seventh power

Which of the following verbal expressions represents x 2 + 2x? Answer Now 1.the sum of a number squared and twice a number 2.the sum of a number and twice the number 3.twice a number less than the number squared 4.the sum of a number and twice the number squared

Which of the following expressions represents four less than the cube of a number? Answer Now 1.4 – x – 3x 3.3x – 4 4.x 3 – 4

Evaluate = = 8 2n 7 We can’t evaluate because we don’t know what n equals to!!

Is 3 5 the same as 5 3 ? Evaluate each and find out! 3 5 = = = = ≠ 125 They are not the same!

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