Question

2x + 5y = 15
5x + 10y = 35

Answer 1

5y=15-2x
y=3-(2/5)x

5x+10(3-(2/5)x) = 35
5x+30-4x = 35
x+30 = 35
x = 5

Plug in x into either formula and you get...

2(5)+5y = 15
10 + 5y = 15
5y = 5
y = 1

Therefore, x = 5, y = 1

Answer 2

multiply first equation with 2

4x+10y=30............(1)
5x+10y=35.............(2)

subtract 2nd equation from 1st one:
-x=-5
x=5

now put the value of x in any one of the above equations......
4(5)+10y=30
10y=30-20
10y=10
y=1

Answer 3

thanks