Question

what is the solution to the system of equations? y = 2x – 3.5 x – 2y = –14 (–7, 3.5) (3.5, –7) (7, 10.5) (10.5, 7)

Answer 1

y=2x-3.5
x-2y=-14
Solving by substitution by x in equation II the subject of the formula;
x=2y-14
Replacing in the first equation;
y=2(2y-14)-3.5
y=4y-28-3.5
y=4y-31.5
y-4y=-31.5
-3y=-31.5
y=
`(-31.5)/(-3)`
y=10.5

Answer 2

we have the system of equations

`y=2x-3.5` --------> equation
`1`

`x-2y=-14` --------> equation
`2`

Multiply by
`2` equation
`1`

`2y=4x-7` --------> equation
`3`

Adds equation
`2` and equation
`3`

`x-2y=-14 \\ 2y=4x-7\\ --------\\ x=-14+4x-7\\ 4x-x=14+7\\ 3x=21\\ x=7`

Find the value of y

`y=2x-3.5`

`y=2*7-3.5`

`y=10.5`

the solution of the system is the point
`(7,10.5)`

therefore

the answer is

`(7,10.5)`