Multiplication and Division One-Step Equations Multiplication and Division January 3, 2018

One-Step Equations Review To solve an equation, we must get the variable by itself on one side of the equal sign. Solving equations is like keeping a scale balanced – whatever is done to one side of the equation must be done to the other side.

Division Property of Equality One-Step Equations Key Concept Division Property of Equality If you divide each side of an equation by the same nonzero number, the two sides remain equal. Arithmetic 6 = 6 6 6 3 = 3 2 = 2 Algebra 2X = 6 2X 6 2 = 2 X = 3 Example

One-Step Equations More Examples 1.) 3X = -9 3X = -9 3 3 X = -3 3 3 X = -3 2.) 24 = -8X 24 = -8X -8 -8 -3 = X

One-Step Equations Try these. Write the middle step and solve. a. ) 4X = -16 b.) -1X = 9 c.) 7 = 4X d.) 12X = 3 4X ÷ 4 = -16 ÷ 4 -1X ÷ -1 = 9 ÷ -1 7 ÷ 4 = 4X ÷ 4 12X ÷ 12 = 3 ÷ 12 X = -4 X = -9 1 ¾ = X X = ¼

Multiplication Property of Equality One-Step Equations Key Concept Multiplication Property of Equality If you multiply each side of an equation by the same number, the two sides remain equal. Algebra X = -6 2 X2 = -62 X = -12 Arithmetic 5 = 5 52 = 52 10 = 10 Example

One-Step Equations Try these. Write the middle step and solve. a.) X÷3 = 9 b.) X ÷ -4 = 7 c.) X ÷ 3 = -1 d.) 4 = X ÷ 4 X ÷ 3•3 = 9•3 X ÷ -4•-4 = 7•-4 X ÷ 3•3 = -1•3 4•4 = X ÷ 4•4 X = 27 X =-28 X = -3 16 = X

Copy and solve the following equations. 4X = 15 X ÷ 2 = -8 9 - X = -1 -12 + X = 0 -X ÷ 3 = 4 X + 5 = 5 X - 4 = 4 -X = 5 X + 50 =-50 X ÷ 5 = -55 x = 3.75 x = 0 x = -16 x = 8 x = 10 x = -5 x = 12 x = -100 x = -12 x = -275