In a class test, the sum of the marks obtained by a student in mathematics and science is 28 - Maths - Quadratic Equations

Question

In a class test, the sum of the marks obtained by a student in
mathematics and science is
28 Had he got 3 marks more in mathematics and 4 marks less in
science, the product of
the marks would have been 180 Find his marks in two subjects

Varun Rawat · Accepted Answer

Dear Student,

Let the marks obtained in Mathematics = xLet the marks obtained in Science = yNow, according to first condition :    x + y = 28⇒y = 28-x         
1Now, marks obtained in Maths = x + 3Marks obtained in Science = y-4Now, according to second condition :   x+3y-4 = 180⇒xy-4x+3y-12 = 180⇒x28-x-4x+328-x = 192     [Using 1]⇒28x - x2 - 4x + 84 - 3x = 192⇒-x2 + 21x  - 108 = 0⇒x2 - 21x + 108 = 0⇒x2 - 12x - 9x + 108 = 0⇒xx-12-9x-12 = 0⇒x-9x-12 = 0⇒x = 9   or   x = 12When x = 9; y = 28 - 9 = 19When x = 12; y = 28 - 12 = 16So, marks obtained in Maths = 9, then marks obtained in Science = 19So, marks obtained in Maths = 12, then marks obtained in Science = 16Regards

In a class test, the sum of the marks obtained by a student in mathematics and science is 28. Had he got 3 marks more in mathematics and 4 marks less in science, the product of the marks would have been 180. Find his marks in two subjects.

In a class test, the sum of the marks obtained by a student in mathematics and science is
28. Had he got 3 marks more in mathematics and 4 marks less in science, the product of
the marks would have been 180. Find his marks in two subjects.