Question

What is the solution of the system of equations? {4x−3y=15 2x+2y=4 Enter your answer in the boxes.

Answer 1

x = 3 & y = -1

Explanation:

If we multiply the 2nd equation given by -2, then add the 2 equation, we will eliminate x and solve for y. The process is shown below:

`(-2)(2x+2y=4)\\=-4x-4y=-8\\---------\\4x-3y=15\\+\\-4x-4y=-8\\--------\\=-7y=7\\y=-1`

We have y = -1.

Now substituting this value of y into the first equation, we can solve for x. Shown below:

`4x-3y=15\\4x-3(-1)=15\\4x+3=15\\4x=12\\x=3`

So we have x = 3

Answer 2

`x=3`

`y=-1`

Explanation:

we are given system of equations as

`4x-3y=15`

`2x+2y=4`

Firstly, we will solve for y from second equation

`2(x+y)=4`

`x+y=2`

we can isolate y

`y=2-x`

now, we can plug it into first equation

and we get

`4x-3(2-x)=15`

now, we can solve for x

`7x-6=15`

`7x=21`

`x=3`

now, we can find y

`y=2-3`

`y=-1`

So, solution is

`x=3`

`y=-1`