Praxis Core Academic Skills for Educators: Mathematics (5733)Algebra and FunctionsEasy
A botanist is cultivating a new hybrid plant. The height of the plant, H(d), in centimeters, after 'd' days is modeled by the function H(d) = 0.5d + 10. What is the predicted height of the plant after 14 days?
- A27 cm
- B24 cm
- C15 cm
- D17 cm
Show answer & explanationAnswer & explanation
Correct answer: D. 17 cm
To find the predicted height, substitute d=14 into the given function H(d) = 0.5d + 10. This calculates H(14) = 0.5(14) + 10 = 7 + 10 = 17.
Why the other options are wrong
- A. This could result from a calculation error, such as mistaking 0.5 * 14 as 17 or adding 17 to 10 incorrectly.
- B. This might result from incorrectly multiplying or adding, perhaps 0.5 * 14 + 10 = 7 + 10 = 17, or if the initial height was 17 and rate was 0.5.
- C. This would be the height if the growth rate were 0.35 cm/day, or if d was 10.
Evaluating Linear Functions
Evaluating a linear function means substituting a given input value into the function's equation to find the corresponding output value.
- Linear functions are of the form f(x) = mx + b.
- The input is typically represented by 'x' (or 'd' in this case).
- The output is represented by 'f(x)' (or 'H(d)').
Memory trick: Plug in the day, get the height display!