A two-variable linear equation can add two groups’ contributions to one total. Match each coefficient to the group size given in the problem, then use the total’s units to work out what its letter means. The key trap is confusing a per-unit amount with either the group’s size or its total contribution.
Hints
- Hint 1
The total is measured in kilograms, so each term being added must also represent kilograms of fertilizer. The acres belong to Silver barley. Which term gives Silver’s contribution?
- Hint 2
Per acre means kilograms divided by acres, a unit rate. If acres times gives Silver’s total kilograms, what units must have so the acres cancel?
Step-by-step
Match the term, then follow the units
Step 1Identify Silver’s part of the total
No Desmos needed. You’re interpreting a letter, not solving for a number.
The in matches the 28 Silver acres. In , the two terms, or amounts being added, make the total fertilizer. So is Silver’s total kilograms, while is Gold’s.
- Step 2
Read what one Silver acre needs
For acres times to give kilograms, must be in kilograms per acre:
The coefficient counts the acres; the letter gives the amount for one acre. So is the kilograms of fertilizer required per acre of Silver barley. Choice B.