Question

x+3y=1
-5x+4y=-15 linear system by using elimination

Answer 1

eliminate x from the secon equation by changing the first equation to:
x = 1 - 3y

Answer 2

x + 3y = 1 --->(5)x + 3y = 1
-5x + 4y =- 15
-----------------
5x + 15y = 5 (result of multiplying by 5)
-5x + 4y = - 15
-----------------add
0 + 19y = - 10
19y = -10
y = - 10/19

now sub - 10/19 in for y
x + 3y = 1
x + 3(-10/19) = 1
x - 30/19 = 1
x = 30/19 + 1
x = 30/19 + 19/19
x = 49/19

check...
x + 3y = 1
49/19 + 3(-10/19) = 1
49/19 - 30/19 = 1
19/19 = 1
1 = 1 (correct)

x = 49/19 and y = -10/19

Answer 3

thanks :)

Answer 4

not a problem...glad i could help :)