Advertisements
Advertisements
Question
Solve the quadratic equation 2x2 + 5x + 2 = 0 using formula method.
Advertisements
Solution
2x2 + 5x + 2 = 0
Comparing the given equation with ax2 + bx + c = 0
a = 2, b = 5, c = 2.
b2 − 4ac = 52 − 4 (2)(2)
= 25 - 16
= 9
By Formula Method,
x = `(-b +- sqrt(b^2 - 4ac))/(2a)`
x = `(-5 +- sqrt(9))/(2(2))`
= `(-5+-3)/4`
= `(-5+3)/4` or x = `(-5-3)/4`
x = `(-2)/4` or x = `(-8)/4`
∴ x = `(-1)/2`
x = −2
APPEARS IN
RELATED QUESTIONS
Complete the following activity to solve the given quadratic equation by formula method.
2x2 + 13x + 15 = 0
Activity: 2x2 + 13x + 15 = 0
a = (______), b = 13, c = 15
b2 – 4ac = (13)2 – 4 × 2 × (______)
= 169 – 120
b2 – 4ac = 49
x = `(-"b" +- sqrt("b"^2 - 4"ac"))/(2"a")`
x = `(- ("______") +- sqrt(49))/4`
x = `(-13 +- ("______"))/4`
x = `(-6)/4` or x = `(-20)/4`
x = (______) or x = (______)
If `(5sqrt(2) + 3sqrt(3)) - (6sqrt(2) - 7sqrt(3)) = asqrt(2) + bsqrt(3)`, then find a and b.
Solve: 7x2 – 30x – 25 = 0
Solve the quadratic equation: 16x2 + 24x + 9 = 0.
Solve the quadratic equation 7x2 + 9x + 2 = 0 by the quadratic formula.
Solve the following quadratic equation by the formula method:
x2 + 10x + 2 = 0
Solve the following quadratic equation by formula method:
3m2 − m − 10 = 0
