5x = 2x + 21
x = 7
Write an Equation and Solve. Julie is 3 years older than her sister. Julie's age is 11 years old. How old is her sister?
n = Julie's sister's ag. n + 3 = 11
n = 8. Julie's sister is 8 years old.
3x + 13 = 8x - 2
x = 3
Write an Equation and Solve. A family bought 7 NB t-shirts for a total of $90.93. Each t-shirt cost the same amount. What is the cost of each t-shirt?
n = # of t-shirts. 7n = 90.93
n = 12.99. Each t-shirt cost $12.99
5x + 9 - x = 7 - 2x
x = -1/3
4(y - 2) = 5y + 8 - y
No Solution!
Write an Equation and Solve. Tyler has 4 boxes of apples. Each box has the same number of apples. After Tyler eats 1 apple and gives 2 away, there are 109 apples remaining. How many apples were originally in each box ?
a = # of apples in each box 4a - 3 = 109
a = 28. There were 28 apples in each box.
-2(x + 3) = 4(5 - x)
x = 13
6(m+2) + 18 = 4m + 2(m+15)
Infinitely Many Solutions!
Write an Equation and Solve. A square with side length of 3x has the same perimeter as an equilateral triangle with side length of 2x + 4. What is the perimeter of each shape?
4(3x) = 3(2x + 4). 12x = 6x + 12. x = 2
Each shape has a perimeter of 24 units
78=3c + 12 - c + 4
c = 31
x - 2(6 - x) = 8x - (x + 6)
x = -3/2
x/2 - (2x)/3 + 2 = x/4
x = 24/5
Write an Equation and Solve. Integers that are one after another are called consecutive integers. Using variables, three consecutive integers are n, n + 1, and n + 2. The sum of three consecutive integers is 48. What are the integers?
n + (n + 1) + (n + 2) = 48. n = 15
The integers are 15, 16, and 17.