Question

Solve the following simultaneous equation please.

Use either addition, subtraction, or substitution.

4x+2y=26
4x-3y=51

Answer 1

I shall use subtraction because I see two like
terms of the same value (4x).

Set them up as a vertical subtraction problem and subtract down.

4x+2y=26
-(4x-3y=51)
___________
5y=-25

Solve for y.

y=-5

Plug this value of y into either original equation and solve for x.

4x+2(-5)=26
4x-10=26
4x=36

x=9

Therefore, the solution is (9, -5).

Answer 2

`\left \{ {{4x+2y=26} \atop *(-1)} \right. \\\\ \left \{ {{4x+2y=26} \atop {-4x+3y=-51}} \right. \\\\+----\\addition\\\\ 5y=-25\ \ \ | divide\ by\ 5\\\\ y=-5\\\\ 4x=26-2y\ \ \ | divide\ by\ 4\\\\x=(13-y)/(2)=(13+5)/(2)=9\\\\Solution:\\x=9\ and\ y=-5`