Solving Equations using Addition & Subtraction
7 + b = -1
-8
8t = -32
t = -4
32 is the sum of a number x and 9.
equation: 32 = x + 9, x = 23
You make $2 for every newspaper you sell. How many newspapers do you have to sell in order to buy a $36 video game? Write an equation and solve.
2n = 36
n = 18
You must sell 18 newspapers.
4b + 3 = -9
b = -3
8 = 12 + z
-4
-3k = 15
k = -5
42 less than x is -50
equation: x - 42 = -50 x = -8
The temperature of dry ice is -109 degrees F. This is 180 degrees F less than the outside temperature. What is the outside temperature? Write and equation & solve.
t - 180 = -109
t = 71
11 = -3x + 2
x = -3
x - (-4) = -9
x = -13
-10 = -b/4
b = 40
A number divided by -8 is 7.
equation: x/-8 = 7 x=-56
The difference in elevation of a helicopter and a submarine is 18 meters. The elevation of the submarine is -7 meters. What is the elevation of the helicopter? Write an equation & solve.
h - (-7) = 18
h = 11
4x -(-5) = 17
x = 3
x + (-5) = -1
x = 4
1/2 g = -12
g = -24
The product of 15 and a number is -75.
equation: 15x = -75, x = -5
In a school election half of the students vote. There are 460 ballots. Write and solve an equation to find the total number of students in the school.
1/2s = 460
s = 920 students
-1/3x + 2 = 9
x = -21