I have reviewed the worksheet provided. It contains 20 algebra problems where you need to find the value of an expression by substituting a given number for a letter (variable). Since the image already shows the correct answers in red, I will walk through the logic used to solve them so you can understand how to do it yourself on similar problems.
Here is the step-by-step breakdown of how these problems are solved:
The General Rule:
To solve these, look at the "Expression" column and the "When" column. The "When" column tells you what number to replace the letter with. Then, just do the math.
Examples from the sheet:
*
Problem 1: Expression is `2a` and `a = 5`.
* Replace 'a' with 5.
* Equation: `2 x 5`
* Answer: `10`
*
Problem 4: Expression is `d ÷ 3` and `d = 24`.
* Replace 'd' with 24.
* Equation: `24 ÷ 3`
* Answer: `8`
*
Problem 6: Expression is `f - 15` and `f = 100`.
* Replace 'f' with 100.
* Equation: `100 - 15`
* Answer: `85`
*
Problem 16: Expression is `4 - p` and `p = 0.5`.
* Replace 'p' with 0.5.
* Equation: `4 - 0.5`
* Answer: `3.5`
*
Problem 20: Expression is `½ t` and `t = 7`.
* Replace 't' with 7.
* Equation: `½ x 7` (or half of 7)
* Answer: `3 ½` or `3.5`
All the calculations in the answer key shown in the image are correct based on this method.
Final Answer:
The worksheet demonstrates how to evaluate algebraic expressions by substitution. For every problem, you simply take the number given for the variable (the letter) and plug it into the expression to solve the math equation. For example, if you see `2a` and `a=5`, you calculate `2 x 5` to get `10`. All answers listed in the red text in your image are correct.
Parent Tip: Review the logic above to help your child master the concept of 6th grade math expressions worksheet.
