Practice and Problem-Solving Exercises
A Practice
See Problem 1.
Solve each equation.
-
h
−
12
=
6
h minus 12 equals 6
-
−
x
3
=
27
negative , x over 3 , equals 27
-
4
t
=
48
4 t equals 48
-
22
+
r
=
36
22 plus r equals 36
See Problem 2.
Solve each equation. Check your answer.
-
7
w
+
2
=
3
w
+
94
7 w plus 2 equals 3 w plus 94
-
15
−
g
=
23
−
2
g
15 minus g equals 23 minus 2 g
-
43
−
3
d
=
d
+
9
43 minus 3 d equals d plus 9
-
5
y
+
1.8
=
4
y
−
3.2
5 y plus 1.8 equals 4 y minus 3.2
-
6
a
−
5
=
4
a
+
2
6 eh minus 5 equals 4 eh plus 2
-
7
y
+
4
=
3
−
2
y
7 y plus 4 equals 3 minus 2 y
-
5
c
−
9
=
8
−
2
c
5 c minus 9 equals 8 minus 2 c
-
4
y
−
8
−
2
y
+
5
=
0
4 y minus 8 minus 2 y plus 5 equals 0
-
6
(
n
−
4
)
=
3
n
6 open n minus 4 close equals 3 n
-
2
−
3
(
x
+
4
)
=
8
2 minus 3 open x plus 4 close equals 8
-
5
(
2
−
g
)
=
0
5 open 2 minus g close equals 0
-
2
(
x
+
4
)
=
8
2 open x plus 4 close equals 8
See Problem 3.
Write an equation to solve each problem.
-
Bus Travel Two buses leave Houston at the same time and travel in opposite directions. One bus averages 55 mi/h and the other bus averages 45 mi\h. When will they be 400 mi apart?
-
Aviation Two planes left an airport at noon. One flew east and the other flew west at twice the speed. After 3 hours the planes were 2700 mi apart. How fast was each plane flying?
-
Geometry The length of a rectangle is 3 cm greater than its width. The perimeter is 24 cm. What are the dimensions of the rectangle?
See Problem 4.
Determine whether the equation is always, sometimes, or never true.
-
5
x
+
3
−
2
x
=
7
x
+
3
5 x plus 3 minus 2 x equals 7 x plus 3
- 2(5x + 4) = 10x + 6
-
2
3
x
+
4
=
2
x
2 thirds , x plus 4 equals 2 x
-
6
x
−
12
+
2
x
=
3
+
8
x
−
15
6 x minus 12 plus 2 x equals 3 plus 8 x minus 15