Hello,
To solve this system of equations, we want to add or subtract the equations so that either x or y cancels out.
We can multiply the first equation by -2, so that 5y will become -10y, and then add the equation with the second so -10y and 10y will cancel out.
Multiplying the first equation by -2, we get:
-4x - 10y = -30
Add this to the second equation and we get:
x = 5
So, we have x = 5. However, we should plug it into both equations to solve for y and make sure both answers check out.
Doing this for the first equation, we have:
2(5) + 5y = 15
10 + 5y = 15
Subtract 10 from both sides to get:
5y = 5
Divide by 5 on both sides to get:
y = 1
We will now see if x = 5 and y = 1 works for the second equation.
5x + 10y = 35
5(5) + 10(1) = 35
35 = 35, checks out
So, x = 5 and y = 1.
Option choice B is correct.
Hope this helps!