Solve the following simultaneous equation: 3x+2y=20 and x+4y=20

We are going to try to eliminate one of the variables in one of the equations. This can be done by rearranging the second equation to x=20-4y. And then substituting x into the first equation.3x+2y=20 => 3*(20-4y)+2y=20 => 60-12y+2y=20 Then we separate constants and variables:=> -10y=-40 => y=(-40)/(-10) => y=4We have found y! Now it's easy to find x, using the equation x=20-4y => x=20-4*4 => x=4So the numbers which satisfy the two equations simultaniously are x=4 and y=4.

SK
Answered by Stephanie K. Maths tutor

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