Digital SATMath: AlgebraEasy
A scientist is studying the relationship between the temperature (T) in Celsius and the resistance (R) of a certain material. The relationship is given by the equation R = 0.5T + 20. If the resistance is measured to be 32.5 ohms, what is the temperature in Celsius?
- A30 °C
- B25 °C
- C20 °C
- D15 °C
Show answer & explanationAnswer & explanation
Correct answer: B. 25 °C
This is a linear equation where we need to solve for T. Given R = 32.5, substitute this into the equation: 32.5 = 0.5T + 20. Subtract 20 from both sides: 12.5 = 0.5T. Divide by 0.5: T = 12.5 / 0.5 = 25. So, the temperature is 25 °C.
Why the other options are wrong
- A. Incorrect. This would be if 0.5T = 15.
- C. Incorrect. This would be if 0.5T = 10.
- D. Incorrect. This would be if 0.5T = 7.5.
Solving Linear Equations
The process of finding the value(s) of the variable(s) that make a linear equation true.
- Involves isolating the variable using inverse operations.
- Operations (addition, subtraction, multiplication, division) must be applied to both sides.
- The goal is to get the variable by itself on one side of the equation.
Memory trick: Balance the scales, isolate the unknown, step by step, until it's shown.