Advertisements
Advertisements
प्रश्न
Suyash scored 10 marks more in second test than that in the first. 5 times the score of the second test is the same as square of the score in the first test. Find his score in the first test.
उत्तर
Let the score in the first test be x.
Suyash's score in second test is 10 more than that in the first.
So, his score in the second test = x + 10
5 times the score of the second test is the same as square of the score in the first test.
\[5\left( x + 10 \right) = x^2 \]
\[ \Rightarrow 5x + 50 = x^2 \]
\[ \Rightarrow x^2 - 5x - 50 = 0\]
\[ \Rightarrow x^2 - 10x + 5x - 50 = 0\]
\[ \Rightarrow x\left( x - 10 \right) + 5\left( x - 10 \right) = 0\]
\[ \Rightarrow \left( x + 5 \right)\left( x - 10 \right) = 0\]
\[ \Rightarrow x = 10, - 5\]
The score is not negative so, Suyash scored 10 marks in first test.
APPEARS IN
संबंधित प्रश्न
If one root of the equation` 3x^2-10x+3=0 is 1/3` then the other root is
(a) `-1/3` (b) `1/3` (c)`-3` (d)`3`
The roots of the equation 2x^2-6x+7=0 are
(a) real, unequal and rational (b) real, unequal and irrational (c) real and equal (d) imaginary
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
Find the roots of the quadratic equation `2x^2-x-6=0`
If the roots of the quadratic equation `px(x-2)+=0` are equal, find the value of p
Find the value of k so that the quadratic equation` x^2-4kx+k=0`
has equal roots.
Decide whether the following equation is quadratic equation or not.
`"y"^2 + 1/"y" = 2`
Decide whether the following equation is quadratic equation or not.
\[x + \frac{1}{x} = - 2\]
Write the following equation in the form ax2 + bx + c = 0, then write the values of a, b, c for the equation.
(x – 1)2 = 2x + 3
Pratik takes 8 hours to travel 36 km downstream and return to the same spot. The speed of boat in still water is 12 km. per hour. Find the speed of water current.
Choose the correct answer for the following question.
For \[\sqrt{2} x^2 - 5x + \sqrt{2} = 0\] find the value of the discriminant.
Solve the following quadratic equation.
(2x + 3)2 = 25
Find the value of m so that the quadratic equation mx (x − 7) + 49 = 0 has two equal roots.
Which of the following is a quadratic equation ?
If P(y) = y² - 2y + 5, find P(2) .
Solve any two of the following.
Solve : `3x+y=14 ; x-y=2`
When the son will be as old as his father today, the sum of their ages then will be 126 years. when the father was as old his son is today. The sum of their ages was 38 years. Find their presents ages.
In a right-angled triangle, altitude is 2 cm longer than its base. Find the dimensions of the right-angled triangle given that the length of its hypotenuse is 10 cm.
Let p and q be two positive numbers such that p + q = 2 and p4 + q4 = 272. Then p and q are roots of the equation ______.
