Question

Solve the following system of equations. x - 2y = 5 2x - 4y = 10

Answer 1

x - 2y = 5
2x - 4y = 10

solve 1 equation for either variable

x - 2y = 5
x = 5 + 2y

so now we can substitute that into the second equation

2(5 + 2y) - 4y = 10

(see how only "y" is left? that's what we're solving for)

10 + 4y - 4y = 10
10 = 10

y = 0

if this is true...sub it back into the first equation to solve for x

x - 2(0) = 5
x - 0 = 5
x = 5

now check both in the second equation

2x - 4y = 10
2(5) - 4(0) = 10
10 - 0 = 10
10 = 10? yes

so
y = 0
x = 5