Jaxon has $65 in his savings account. He deposits $15 every week. His father also deposits $25 into the account every time Jaxon
mows the lawn. His savings account balance can be shown with the following expression: 65 + 15w + 25m Part A: Identify a coefficient, a variable, and a constant in this expression. (3 points) Part B: If Jaxon saves for 20 weeks and mows the lawn 3 times, how much will he have in his account? Show your work to receive full credit. (4 points) Part C: If Jaxon had $75 in his savings account, would the coefficient, variable, or constant in the expression change? Why? (3 points)
Part A: A coefficient can be either '15' or '25'. A variable can be either 'w' or 'm'. A constant is 65.
Part B: Simply substitute, or plug-in, the numbers and solve. ***Step 1: 65+15w+25m --> 65+15(20)+25(3) You do this because you are substituting the 'w' for the number of weeks that Jaxon saved up for, which is 20, and the 'm' for the number of times that Jaxon mowed the lawn, which is 3. ***Step 2: 65+15(20)+25(3) --> 65+300+75 Begin to solve, using PEMDAS, or whichever acronym you learned. Remember, if you are using PEMDAS, recall that the order is Parenthesis, Exponents, Multiplication/Division (whichever comes first), and Addition/Subtraction (whichever comes first). Here, I checked for parenthesis. I did find parenthesis, however, they do not have any expressions inside of them, meaning that these parenthesis are for multiplying, and not for stating order. So, you skip parenthesis. Next, you check for exponents, which you find none of, so you skip over that. Now, we get to multiplying/dividing, so you multiply the 15 and the 20 to get 300, and the 25 and 3 to get 75. ***Step 3: 65+300+75 --> 440 Now, we get to addition. You simply add everything up to get your final answer: $440.
Part C: If Jaxon had $75, then yes, the coefficients would change. By subtracting $65 from $75, we can see that the total amount of money from Jaxon's deposits and his lawn-mowing money is $10. Jaxon already deposits $15 a week, meaning that, while using the current equation, Jaxon CANNOT have $75 in his bank account. We can change the equation so that Jaxon is able to have $75 in his savings account. You can change the coefficient of 15 to 10, and the other coefficient of 25 to 0. Now Jaxon is able to have $75 in his savings account.
