2-Step Equations

What??? I just learned 1-step! Relax. You’ll use what you already know to solve 2-step equations.

Solving Two-Step Equations To find the solution to an equation we must isolate the variable. In other words, get the variable on one side of the equation by itself. We isolate the variable by performing operations that will eliminate (cancel) the other numbers from the expression.

Solving Two-Step Equations We have seen how to eliminate a constant (Addition Property of Equality) & how to eliminate a coefficient (Multiplication Property of Equality). What if an equation has both a constant and a coefficient to be eliminated? This is called a Two-Step Equation.

STEP 1 The first step will always be either adding or subtracting. (Think: Order of Operations backwards)

STEP 2 The second step will always be either multiplying or dividing.

8x + 5 = 61 This problem has addition, so we need to subtract first. - 5 Whatever we do on one side, we have to do on the other. 8x 56= EX1) This problem has multiplication, so we need to divide now. 8 8 x = 7 8x + 5 = 61 8(7) + 5 = = 61 61= 61 Check

EX2) 3a - 8 = 4 This problem has subtraction, so we need to add first a 12 = 3 3 a = 4 This problem has multiplication, so we need to divide now. 3a - 8 = 4 3(4) - 8 = = 4 4= 4 Check

EX3) z + 2 = 26 6 This problem has addition, so we need to subtract first = z6z6 This problem has division, so we need to multiply now. z = z + 2 = = = = 26 Check

EX4) m - 10 = 15 5 This problem has subtraction, so we need to add first = m5m5 This problem has division, so we need to multiply now. m = m - 10 = = = 15 15= 15 Check

Assignment Page , 9-11 show work on a separate sheet of paper

Notes start here

2-Step Equations Date ______________

8x + 5 = 61 EX1)

EX2) 3a - 8 = 4

EX3) z + 2 = 26 6

EX4) m - 10 = 15 5