Advertisements
Advertisements
Question
If `x=-1/2` is a solution of the quadratic equation `3x^2+2kx-3=0`
Find the value of k.
Solution
It is given that x=`-1/2` is a solution of the quadratic equation `3x^2+2kx-3=0`
∴` 3x((-1)/2)^2+2kxx((-1)/2)-3=0`
⇒`3/4-k-3=0`
⇒` k=(3-12)/4=9/4`
Hence, the value of k is `-9/4`
APPEARS IN
RELATED QUESTIONS
If one root of `5x^2+13x+k=0` be the reciprocal of the other root then the value of k is
`(a)0 (b)1 (c)2 (d)5`
The roots of the equation `2x^2-6x+3=0` are
(a) real, unequal and rational (b) real, unequal and irrational (c) real and equal (d) imaginary
If the roots of the quadratic equation `px(x-2)+=0` are equal, find the value of p.
The total cost of a certain length of a piece of cloth is Rs 200. If the piece was 5 m longer and each metre of cloth costs Rs 2 less, the cost of the piece would have remained unchanged. How long is the piece and what is its original rate per metre ?
Decide whether the following equation is quadratic equation or not.
x2 + 5x – 2 = 0
Write the following equation in the form ax2 + bx + c= 0, then write the values of a, b, c for the equation.
x2 – 9 = 13
Mr. Kasam runs a small business of making earthen pots. He makes certain number of pots on daily basis. Production cost of each pot is Rs 40 more than 10 times total number of pots, he makes in one day. If production cost of all pots per day is Rs 600, find production cost of one pot and number of pots he makes per day.
Choose the correct answer for the following question.
The roots of x2 + kx + k = 0 are real and equal, find k.
If in an A. P., d = 10, find t6 - t2.
Alka spends 90 % of the amount sent to her and saves Rs. 120 per month. Find the amount sent to her per month.