SOLUTION: Graphing the system: x + 4 = 11 x -4 = 5

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Question 263992: Graphing the system:
x + 4 = 11
x -4 = 5
Answer by JBarnum(2146) About Me  (Show Source):
You can put this solution on YOUR website!
x + 4 = 11
x -4 = 5
solve for x
x=7
x=9
im just doing this part below so i can input the graph
same as x-7=0 x-9=0
(x-7)(x-9)
x^2-16x+63=0 A=1 B=-16 C=63 VIEW the graph below
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation az%5E2%2Bbz%2Bc=0 (in our case 1z%5E2%2B-16z%2B63+=+0) has the following solutons:

z%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%28-16%29%5E2-4%2A1%2A63=4.

Discriminant d=4 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--16%2B-sqrt%28+4+%29%29%2F2%5Ca.

z%5B1%5D+=+%28-%28-16%29%2Bsqrt%28+4+%29%29%2F2%5C1+=+9
z%5B2%5D+=+%28-%28-16%29-sqrt%28+4+%29%29%2F2%5C1+=+7

Quadratic expression 1z%5E2%2B-16z%2B63 can be factored:
1z%5E2%2B-16z%2B63+=+1%28z-9%29%2A%28z-7%29
Again, the answer is: 9, 7. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B-16%2Ax%2B63+%29