Advertisements
Advertisements
Question
One of the roots of equation x2 + 5x + a = 0 is – 3. To find the value of a, fill in the boxes.
Since, `square` is a root of equation x2 + 5x + a = 0
∴ Put x = `square` in the equation
⇒ `square^2 + 5 xx square + a` = 0
⇒ `square + square + a` = 0
⇒ `square + a` = 0
⇒ a = `square`
Solution
Since, – 3 is a root of equation x2 + 5x + a = 0
∴ Put x = – 3 in the equation
⇒ – 32 + 5 × – 3 + a = 0
⇒ 9 + – 15 + a = 0
⇒ – 6 + a = 0
⇒ a = 6
APPEARS IN
RELATED QUESTIONS
If the roots of 2x2 - 6x + k = 0 are real and equal, find k.
If α and β are the roots of the quadratice equation x²- 2x - 7= 0, find the
value α² + β²
If one root of the quadratic, x2 - 7x + k = 0 is 4. then find the value of k.
Convert the following equations into simultaneous equations and solve:
`sqrt("x"/"y") = 4, 1/"x" + 1/"y" = 1/"xy"`
Choose the correct alternative answer for the following sub questions and write the correct alphabet.
Degree of quadratic equation is always ______
To decide whether 1 is a root of quadratic equation x2 + 4x – 5 = 0 or not, complete the following activity.
Activity: When x = (______)
L.H.S. = 12 + 4(______) – 5
= 1 + 4 – 5
= (______) – 5
= ______
= R.H.S
Therefore x = 1 is a root of quadratic equation x2 + 4x – 5 = 0
Roots of a quadratic equation are 5 and – 4, then form the quadratic equation
If the roots of the given quadratic equation are real and equal, then find the value of ‘k’
kx(x – 2) + 6 = 0
Solve the following quadratic equation.
`sqrt(3) x^2 + sqrt(2)x - 2sqrt(3)` = 0
Solve the following quadratic equations by formula method.
5m2 – 4m – 2 = 0
Form a quadratic equation if the roots of the quadratic equation are `2 + sqrt(7)` and `2 - sqrt(7)`
Sum of the roots of the quadratic equation is 5 and sum of their cubes is 35, then find the quadratic equation
Solve the following quadratic equation using formula:
x2 + 10x + 2 = 0
If the sum of the roots of the quadratic equation x2 + kx + 6 = 0 is 6, then the value of k is ______.
If the roots of the quadratic equation x2 + 12x + a = 0 are real and equal, then find the value of a.
If x = `sqrt(7) - 2`, find the value of `(x + 1/x)`.
Is (x – 5) a factor of the polynomial x3 – 5x – 30?
