Writing Equations
I spent $20 at the store. I bought $15 worth of candy. I spent some money on gum (g). Write an addition equation to represent the situation.
15 + g = 20
Solve:
b - 7 = 11
b = 18
Is 4 a solution to the equation:
2c = 14
Explain why or why not.
No. Four is not a solution. If you substitute 4 in for c, 2 x 4 = 8.
8 is not equal to 14. It is not a solution.
What do these symbols represent?
< and >?
< represents "less than"
> represents "greater than"
Solve 3b < 12
b < 4
Cameron spends $30 on ice cream. He buys pints for $4 each. He also buys a gallon of ice cream for $6. Write an addition equation to represent the situation. Use "p" for pints.
4p + 6 = 30
Solve:
10 + g = 32
What is a solution?
A solution is like an answer to an equation. It is a value that makes the statement (equation, inequality) TRUE.
Write the inequality:
Three added to n is less than 14
3 + n < 14
Solve the inequality, four times m is less than or equal to 24.
m is less than or equal to 6.
I earned some cash babysitting. I took that money and I bought a new shirt for $14.50. When I was done shopping, I had $28.50 left. Write a subtraction equation to represent the situation and to find how much I earned, e, babysitting.
e - 14.50 = 28.50
Solve:
5 1/2 = b - 12 1/4
b = 17 3/4
Which of the values is a solution to 2k + 3 = 11
k= 3
k = 4
k =5
k = 4 is a solution.
Write the inequality:
Four times k is greater than 45
4k > 45
Solve 11h > 66
h > 6
On Saturday and Sunday, Mike went running and burned a total of 647. 5 calories. He burned 320 of them on Saturday. Write an addition equation that could be used to find the number of calories burned on Sunday.
320 + s = 647.5
s represents the number of calories burned on Sunday.
Solve:
d/3 = 14
(d divided by 3 equals 14)
d = 42
d - 8.4 = 8.6
Which is a solution?
15, 16, 17
17 is a solution.
If you graph the inequality, d < 13, which direction would the area go? Explain why your answer is correct.
The arrow would go to the left. It would go to the left so anything less than 13 would be included.
t > 29
Together, Annie and Jenny saved $365.50. If Annie saved $215 of that, how much did Jenny save? Create an addition equation that could be used to find how much money "m" that Jenny saved.
215 + m = 365.50
1.75d = 12.25
Solve for d.
d = 7
(2m + 2) + 4 = 16
Which of the following is a solution to the equation?
4, 5, 6, or 7?
5 is the solution.
Explain how you know if the dot in plotting an inequality on a number line is open or closed.
If the inequality is greater than or less than, the dot is open. If it is greater than or equal to or less than or equal to, the dot is closed.
1/2 < w/8
4 < w