Question

$5x - 4y = 8 \\ 7x - 6y = 9$
elimination method​

Answer 1

Solve by Elimination

Let's solve your system by elimination.

$5x−4y=8;7x−6y=9$

Multiply the first equation by 3,and multiply the second equation by -2.

$→3(5x−4y=8)$

$→−2(7x−6y=9)$

Becomes:

$→15x−12y=24$

$→−14x+12y=−18$

Add these equations to eliminate y:

$x=6$

Then solvex=6 for x:

$→x=6$

Now that we've found x let's plug it back in to solve for y.

Write down an original equation:

$→5x−4y=8$

Substitute 6 for x in

$→5x−4y=8$

$→(5)(6)−4y=8$

$→−4y+30=8$

(Simplify both sides of the equation)

$→−4y+30+−30=8+−30$

(Add -30 to both sides)

$→−4y=−22−4y−4=−22−4$

(Divide both sides by -4)

$→y=11/2$

Answer:

$x=6\; and\; y=11/2$