Question

Use the substitution method to solve this system of equations. Choose the correct ordered pair. 2x-y=10. 2x-2y=4

Answer 1

Answer:

(x, y) = (8, 6)

Step-by-step explanation:

given the 2 equations

2x - y = 10 → (1)

2x - 2y = 4 → (2)

rearrange equation (1) expressing y in terms of x

y = 2x - 10 → (3)

Substitute y = 2x - 10 in equation (2)

2x - 2(2x - 10) = 4

2x - 4x + 20 = 4

- 2x + 20 = 4 ( subtract 20 from both sides )

- 2x = - 16 ( divide both sides by - 2 )

x = 8

substitute x = 8 in equation (3)

y = (2 × 8) - 10 = 16 - 10 = 6

solution is (8 , 6)

Answer 2

ANSWER

The correct ordered pair is
$(8,6).$



EXPLANATION

The given equations are
$2x - y = 10$


We make y the subject and call it equation (1).


Thus,

$- y = - 2x + 10$


This implies that,


$y = 2x - 10 - - - (1)$


The second equation is

$2x - 2y = 4 - - - (2)$


We substitute equation (1) into equation (2).

$2x - 2(2x - 10) = 4$


We expand brackets to obtain,

$2x - 4x + 20 = 4$


This implies that,

$2x - 4x= 4 - 20$


$- 2x = - 16$

$x = 8$


We put this value in to equation (1) to get,

$y = 2(8) - 10$

$y = 16 - 10$


$y = 6$


The correct orders pair is
$(8,6)$