Which system is equivalent to 5x^2+6y^2=50 7x^2+2y^2=10

Option D

Step-by-step explanation:

This question is incomplete; here is the complete question.

Which system is equivalent to

5x² + 6y² = 50

7x² + 2y² = 10

A. 5x² + 6y² = 50

   -21x²- 6y² = 10

B. 5x² + 6y² = 50

  -21x²- 6y² = 30              

C. 35x²+ 42y² = 250

   -35x²- 10y² = -50

D. 35x² + 42y² = 350

   -35x²- 10y² = -50

In this question system of equations have been given as

5x² + 6y² = 50 (1)

7x² + 2y² = 10 (2)

To solve these equations multiply the equation (2) by (-5)

-35x² - 10y² = -50 (3)

and multiply equation (1) by 7

35x²+ 42y² = 350 (4)

Therefore, system of equations (3) and (4) are the equivalent to the parent system.

This system matches with Option D.

Therefore, Option D is the answer.

distance covered by pamela in 9 l of fuel = 99km

let us apply unitary method here.

distance covered by pamela in 1 l of fuel =99/9 =11 km

now let us find distance covered by pamela if she has 12 l of fuel.

distance covered in 12 l = distance covered in 1 l of fuel * 12

we know that distance covered by here in 1 l is 11 km.

so distance covered in 12 l of fuel = 11*12 = 132 km.