9 + n = 13
9 + n = 13
-9 = - 9
n = 4
m + 15 = 37
m + 15 = 37
- 15 = -15
m = 37 - 15
m = 22
Nine-banded armadillos are always born in groups of 4. If there are 32 babies, what is the number of armadillos? Write an algebraic equation, and let m represent the number of mother armadillos.
4m = 32
/4 = /4
m = 32/4
m = 8 mothers
2x + 1 = 11
2x + 1 = 11
- 1 = -1
2x = 11 - 1
2x = 10
/2 = /2
x = 5
An emperor penguin is 45 inches tall. It is 24 inches taller than a rockhopper penguin. Write and solve an equation to find the height "h" (in inches) of a rockhopper penguin.
h + 24 = 45
- 24 = -24
h = 21 inches
m - 26 = 54
m - 26 = 54
+26 = +26
m = 28
n - 42 = 18
n - 42 = 18
+ 42 = + 42
n = 18 + 42
n = 60
The Empire State Building is 381 m tall. At the Grand Canyon's widest point, 76 Empire State Buildings would fit end to end. Write and solve an algebraic equation to the the width of the Grand Canyon at this point. Define a variable.
Define variable: w = width of grand canyon in meters
m/76 = 381
* 76 = * 76
m = 381 * 76
m = 28,956 meters
3x + 2 = 14
3x + 2 = 14
-2 = - 2
3x = 14 - 2
3x = 12
3x/3 = 12/3
x = 4
9 is the difference of a number n and 7.
9 = n - 7
+7 = +7
n = 16
45x = 180
45x = 180
/45 = /45
x = 4
3n = 15
3n = 15
/3 = /3
n = 15/3
n = 5
Millipedes have 4 legs per segment. The record number of legs on a millipede is 752. Write an algebraic equation and solve it for the number of leg segments the millipede has. Define the variable.
Define: s = number of leg segments
4s = 752
/4 = /4
s = 752/4
s = 188 leg segments
4f - 2 = 14
4f - 2 = 14
+ 2 = + 2
4f = 14 + 2
4f = 16
4f/4 = 16/4
f = 4
Solve: 15 - y = 8
15 - y = 8
+ y = + y
15 = 8 + y
- 8 = -8
7 = y
3.2x = 12.8
3.2x = 12.8
/3.2 = /3.2
x = 4
1/5 x = 30
1/5x = 30
* 5 = * 5
x = 30 * 5
x = 150
Define: a = area of the entire yard
1/12 a = 10
* 12 = * 12
a = 12 * 10
a = 120 sq. yards
x/5 - 1 = 2
x/5 - 1 = 2
x/5 = 2 + 1
x/5 = 3
x = 3 (5)
x = 15
On Saturday, you spend $33, give $15 to a friend, and receive $20 for mowing your neighbor’s lawn. You have $21 left. Write an algebraic equation to represent the amount you started with and solve. Define variable.
m = money you started with
m - 33 - 15 + 20 = 21
m - 48 + 20 = 21
m - 28=21
+28 = +28
m = $49
4/7x = 56
4/7x = 56
/4/7 = / 4/7
x = 56/1 * 7/4
x = 98
h/6.7 = 9.25
h/6.7 = 9.25
* 6.7 = * 6.7
h = 9.25 * 6.7
h = 61.975
DAILY DOUBLE
The height of the 50-milliliter beaker is one-third the height of the 2000-milliliter beaker. The height of the 50-milliliter beaker's height is 6 cm. Write an algebraic equation to find the height h (in centimeters ) of the 2000-milliliter beaker.
1/3h = 6
* 3 = *3
h = 18 cm.
x/2 - 4 = 6
x/2 - 4 = 6
+ 4 = +4
x/2 = 6 + 4
x/2 = 10
* 2 = * 2
2x = 10 (2)
x = 20
The drama club sold all the tickets for its annual production in three days. The club sold 143 tickets the first day and 295 tickets the second day. If the drama club sold 826 tickets, how many did it sell on the third day. Write an algebraic equation and solve for the number of tickets sold on the third day. Define the variable.
Define: t = number of tickets on 3rd day
143 + 295 + t = 826
438 + t = 826
- 438 = - 438
t = 826 - 438
t = 388 tickets