3x + 2y = 8 y = 4x – 7
i need to solve for x and y
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.
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)
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.