Pre Algebra Period 2( Week of October 6)

Two Step Equations 7-1

Use the Addition Property of Equality or the Subtraction Property of Equality to get rid of addition or subtraction
+prop =
-prop =

Then use the Multiplication Property of Equality or the Division Property of Equality to get rid of multiplication or division
xprop =
÷prop=

This is the opposite of Aunt Sally because for solving equations you must work backwards-- or go in reverse!!

3x + 7 = 28
Subtract seven from both sides
-7 = -7 you subtract 7 form both sides so you used the -prop =
3x = 21
NOW Divide both sides by 3
3x/3 = 21/3
x = 7

CHECKING a 2 step equation

You need 3 steps to check also

1) rewrite the equation
3x + 7 = 28
2) substitute your answers and put a "?" over the "="
3) DO THE MATH!! use order of operations
3(7) + 7 ? 28
21 + 7 ? 28
28 = 28