Solving Equations by Combining Like Terms 3x +12 – 4x = 20 Look: There are 2 variable terms … … so, COMBINE LIKE TERMS first. Remember, ‒1x = ‒x but, just leave the 1 there. –1x +12 = 20 – 12 – 12 Look at the variable side, find the constant, and get rid of it first. –1x = 8 2. To get rid of +12, add the opposite (‒12) –1 –1 3. Cancel the opposites … … bring down the variable term …then add. 4. To get rid of the coefficient, ‒1 … … x = –8 … DIVIDE both sides by ‒1

Solving Equations by Combining Like Terms Solve the equation. 3. –8r – 2 + 7r = – 9 –6 = 11w –5w 1. 2. 4p +10 + p = 25 w = – 1 p = 3 r = 7

Solving Equations by using Distributive Property EXAMPLE 3 6n –2(n +1) = 26 Use Distributive property “outer times first”, then 6n –2(n +1) = 26 “outer times second”, Combine like terms. 6n –2n –2 = 26 4n – 2 = 26 + 2 + 2 Add 2 to each side. 4n = 28 Solve. n = 7

Solving Equations by using Distributive Property 1. 2. 3. 3(x – 9) = – 39 –63 = –7(8 – p) 25 = –3(2x + 1) x = or – 4 x = – 4 p = –1