Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Algebra

Question:

If 4x - 3y = 12 and xy = 5, then find the value of $\frac{16 x^2+9 y^2}{8}$.

Options:

33

18

3

44

Correct Answer:

33

Explanation:

We know that,

(a - b)2 = a2 + b2 - 2ab

4x - 3y = 12

= (4x - 3y)2 = 122

= 16x2 + 9y2 - 24xy = 144

= 16x2 + 9y2 - 24 × 5 = 144

= 16x2 + 9y2 - 120 = 144

= 16x2 + 9y2 = 264

$\frac{16 x^2+9 y^2}{8}$ = $\frac{264}{8}$ = 33