Solve an equation using subtraction EXAMPLE 1 Solve x + 7 = 4. x + 7 = 4 Write original equation. x + 7 – 7 = 4 – 7 Use subtraction property of equality: Subtract 7 from each side. x = –3 Simplify. ANSWER The solution is –3.
Dec 23, 2015
Solve an equation using subtractionEXAMPLE 1
Solve x + 7 = 4.
x + 7 = 4 Write original equation.
x + 7 – 7 = 4 – 7 Use subtraction property of equality: Subtract 7 from each side.
x = –3 Simplify.
ANSWERThe solution is –3.
Solve an equation using subtraction
EXAMPLE 1
CHECK Substitute –3 for x in the original equation.
x + 7 = 4 Write original equation.
–3 + 7 = 4? Substitute –3 for x.
4 = 4 Simplify. Solution checks.
Solve an equation using addition
EXAMPLE 2
Solve x – 12 = 3.
Horizontal format Vertical format
x – 12 = 3 Write original equation. x – 12 = 3
Add 12 to each side. + 12 + 12
x = 15 Simplify. x = 15
x – 12 + 12 = 3 + 12
Solve an equation using division
EXAMPLE 3
Solve –6x = 48.
–6x = 48
x = –8
Write original equation.
–6x–6
48–6= Divide each side by –6.
Simplify.
GUIDED PRACTICE for Examples 1, 2, and 3
1. y + 7 = 10
ANSWER 3
Solve the equation. Check your solution.
2. x – 5 = 3
GUIDED PRACTICE for Examples 1, 2, and 3
8ANSWER
Solve the equation. Check your solution.
GUIDED PRACTICE
3. q – 11 = –5
for Examples 1, 2, and 3
6ANSWER
Solve the equation. Check your solution.
GUIDED PRACTICE
4. 6 = t – 2
for Examples 1, 2, and 3
8ANSWER
Solve the equation. Check your solution.
GUIDED PRACTICE
5. 4x = 48
for Examples 1, 2, and 3
12ANSWER
Solve the equation. Check your solution.
GUIDED PRACTICE
6. –65 = –5y
for Examples 1, 2, and 3
13ANSWER
Solve the equation. Check your solution.
GUIDED PRACTICE
7. 6w = –54
for Examples 1, 2, and 3
–9ANSWER
Solve the equation. Check your solution.
GUIDED PRACTICE
8. 24 = –8n
for Examples 1, 2, and 3
–3ANSWER
Solve the equation. Check your solution.