Find the values of x and y that make both equations true 3x+y= 4 4x+y= 10

Answer 1

Hello, Adham,

Rearrange one equation to solve for either x or y, and then substitute it into the second expression.

I used the first equation and rearranged it:

y = 4 - 3x

Now use that definition of y in the second equation:

4x + (4-3x) = 10

1x + 4 = 10

x = 6

This substitution reduced two unknows to just one, so we could find x.

Now use x = 6 in either equation to find y:

y = 4 - 3*6

y = -14

Double check by using these values to see if they fit the original equations.

I hope this helps,

Bob