9.6.5 Practice

For each equation in questions 1 – 5, identify the values of $a$, $b$, and $c$ that you would substitute into the quadratic formula to solve the equation.

1. $3x^2+8x+4=0$

1. What is the value of $a$?

2. What is the value of $b$?

3. What is the value of $c$?

2. $2x^2-5x+2=0$

1. What is the value of $a$?

2. What is the value of $b$?

3. What is the value of $c$?

3. $-<!--\; -\; -->9x^2+13x-1=0$

1. What is the value of $a$?

2. What is the value of $b$?

3. What is the value of $c$?

4. $x^2+x-11=0$

1. What is the value of $a$?

2. What is the value of $b$?

3. What is the value of $c$?

5. $-<!--\; -\; -->x^2+16x+64=0$

1. What is the value of $a$?

2. What is the value of $b$?

3. What is the value of $c$?

1. $4$
2. $-<!--\; -\; -->4$
3. $-<!--\; -\; -->5$
4. $5$
5. $1$
6. $9$
7. $20$

2. $x^2-10x+21=0$

1. $3$
2. $-<!--\; -\; -->7$
3. $21$
4. $-<!--\; -\; -->10$
5. $1$
6. $-<!--\; -\; -->4$
7. $7$

3. $3x^2-5x+1=0$

1. $\frac{13}{6}+\frac{\sqrt{5}}{6}$
2. $-<!--\; -\; -->1$
3. $\frac{5}{6}-<!--\; -\; -->\frac{\sqrt{13}}{6}$
4. $\frac{13}{6}-<!--\; -\; -->\frac{\sqrt{5}}{6}$
5. $-<!--\; -\; -->\frac{18}{6}-<!--\; -\; -->3$
6. $\frac{5}{6}+\frac{\sqrt{13}}{6}$
7. $\frac{18}{6}-<!--\; -\; -->3$

1. What is the value of $a$?

2. What is the value of $b$?

3. What is the value of $c$?

8. $4x^2-3x+11=0$

1. What is the value of $a$?

2. What is the value of $b$?

3. What is the value of $c$?

9. $81-x+5x^2=0$

1. What is the value of $a$?

2. What is the value of $b$?

3. What is the value of $c$?

10. $45x^2+3x=\frac{1}{3}$

1. What is the value of $a$?

2. What is the value of $b$?

3. What is the value of $c$?

11. $121=x^2$

1. What is the value of $a$?

2. What is the value of $b$?

3. What is the value of $c$?

12. $7x+14x^2=42$

1. What is the value of $a$?

2. What is the value of $b$?

3. What is the value of $c$?