Question

4x + 8y=20
3x+6y=15
solve this system of equations

Answer 1

`4x + 8y=20 \ \ \ \ \ : \ \ \ \ \ 3x+6y=15`


`\text{Solve for x in 4x+8y=20}`


`4x+8y=20`


`4(x+2y)=20`


`x+2y= (20)/(4)`


`x+2y=5`


`x=5-2y`


`15=15`


`\text{Infinitely Many Solutions}`

Answer 2

4x=20-8y

x=5-2y now use this value of x in the second equation...

3(5-2y)+6y=15

15-6y+6y=15

15=15 This is true for any y or x value.

So there are infinitely many solutions as the two equations describe the same line.