Digital SAT Math
SAT Math: Find the Sum and Product of the Roots of 5x² - 15x - 7 = 0 (Vieta's Formulas)
• Direct Answer / Key Takeaway
By Vieta's formulas, sum of roots = -b/a = -(-15)/5 = 3.
Exact Question Text
What is the sum of the solutions to the quadratic equation 5x^2 - 15x - 7 = 0?
1. Step-by-Step Formal Solution
- In ax^2 + bx + c = 0, sum of roots = -b/a.
- a = 5, b = -15 => -(-15)/5 = 15/5 = 3.
2. Fast Desmos / Calculator Shortcut
Type solutions in Desmos using quadratic formula and add them: sum equals exactly 3.
3. Distractor Trap Analysis
- Trap A (Sign Flip): Forgetting to reverse inequality or dropping negative sign.
- Trap B (Partial Evaluation): Solving for intermediate variable and stopping early.
- Trap C (Extreme Assumption): Over-inferring beyond textual evidence.
- Option Correct: Accurately satisfies all algebraic and logical constraints.
Ready for Test Day?
Exam readiness starts with your body, not just your textbook. Calculate your Body Readiness Score (0–100) and get daily 10-second micro-protocols tailored to your weakest biological pillar.
Download ExamPeak FreeRelated Exam Questions & Solutions
Digital SAT Math
Bluebook Test 4 Math Module 2 Question 20: y = 3x² - bx + 12 One x-Intercept
Step-by-step solution, fast Desmos shortcuts, and trap distractor analysis for: Bluebook Test 4 Math Module 2 Question 20 y = 3x^2 - bx + 12...
Digital SAT Math
SAT Math: 4x - 6y = 18 and kx + 9y = p Infinitely Many Solutions, Find p/k
How to solve linear systems with constants k and p having infinitely many solutions on Digital SAT Math Module 2....
Digital SAT Math
SAT Math: Find the Maximum Value of f(x) = -2(x - 5)² + 18 in Under 5 Seconds
Step-by-step solution, fast Desmos shortcuts, and trap distractor analysis for: maximum value of f(x) = -2(x - 5)^2 + 18....