Which of these strategies would eliminate a variable in the system of equations?
2x-5y=13
-3x+2y=13

B

Step-by-step explanation:

2x-5y=13(1) × 3

-3x+2y=13(2) × 2

6x - 15y = 39

-6x + 4y = 26

Adding

6x - 6x - 15y + 4y = 13 + 13

Step-by-step explanation:

2x - 5y = 13

-3x + 2y = 13

multiply the top equation by 3 and the bottom one by 2, then add <==

watch...

2x - 5y = 13multiply by 3

-3x + 2y = 13multiply by 2

6x - 15y = 39 (result of multiplying by 3)

-6x + 4y = 26 (result of multiplying by 2)

add

- 11y = 65notice how out x terms were eliminated :)

it's equivalent, so we can say that its equal.

let's call the denominator x and the numerador is 18 less then denominator, x - 18.

multiply

2.x = 5.(x - 18)

2x = 5x - 90

90 = 5x - 2x

90 = 3x

x = 90/3

x = 30

so: