3x + 2y = 8 y = 4x – 7

i need to solve for x and y

Guest Apr 23, 2019

edited by
Guest
Apr 23, 2019

edited by Guest Apr 23, 2019

edited by Guest Apr 23, 2019

#1**0 **

This is a simple algebra problem. You set X to set and get the value for X. You do the same thing for Y.

Once you get these vales, just plug them into your problem.

RandiLaine98 Apr 23, 2019

#2**+1 **

3x + 2y =8 y = 4x-7 SUb second equation in to the first...then solve for x

3x + 2 (4x-7) = 8

3x +8x -14 = 8

11x = 22

x = 2 Use this value of x to sub back in to one of the original equations to find y

y = 4x-7

y = 4(2) - 7

y = 1 so the solution point is (2,1)

ElectricPavlov Apr 23, 2019

#3**-5 **

As listed above, others used substitution, but you can use elimination as another way to solve it

Using substitution is easiest because it already tells you what y is in terms of x

Elimination:

We try to subtract/add the two sentences to remove the extra variable

I can multiply 3x+2y=8 by 4 to get 12x+8y=32

I can them multiply y=4x-7 by 3 to get 3y=12x-21

Now by subtracting these two sentences I can remove the x value

After I get rid of my x value, the y variable will be the only variable left, where we can now solve the Algebra equation.

doorknoob Apr 23, 2019