Chapter 4, Lesson 12


4-12.A add and subtract signed decimals
Evaluate each expression.
a.
—3.1 + (—2.9) b. —9.6 — (—3.8)

4-12.B understand how to solve addition and subtraction equations
For which equation would the Addition Property of Equality be used in the solution?
(a)
x + 4 = 7
(b) 17 = 2x + 7
(c) 12 = x — 5
(d) x — 4 + 9 = 21

4-12.C rewrite subtraction equations as related addition equations
Rewrite each subtraction equation as a related addition equation.
a. y — (—5) = 30 b. 14 = z — 7