SOLUTION: what is x-squared=3x+10?

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Question 428519: what is x-squared=3x+10?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+x%5E2+=+3x+%2B+10+
Subtract +3x+%2B+10+
from both sides
x%5E2+-+3x+-+10+=+0+
The equation now has the form
ax%5E2+%2B+b%2Ax+%2B+c+=+0
Solve using the quadratic equation
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a+=+1
b+=+-3
c+=+-10
x+=+%28-%28-3%29+%2B-+sqrt%28+%28-3%29%5E2-4%2A1%2A%28-10%29+%29%29%2F%282%2A1%29+
x+=+%28+3+%2B-+sqrt%28+9+%2B+40+%29%29+%2F+2+
x+=+%28+3+%2B-+7%29+%2F+2+
+x+=+5+
and
+x+=+-2+
------------
You can check just by rewriting these results:
+x+=+5+
x+-+5+=+0+
and
x+=+-2+
+x+%2B+2+=+0+
Now you can say
+%28x+-+5%29%2A%28x+%2B+2%29+=+0+
+x%5E2+-+3x+-+10+=+0+
OK