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

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

$(7,10.5)$

Answer 2

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=$\frac{-31.5}{-3}$
y=10.5