SOLUTION: solve {{{x^2+3=38+2x}}}

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Question 1150379: solve x%5E2%2B3=38%2B2x
Found 2 solutions by ikleyn, Theo:
Answer by ikleyn(52776) About Me  (Show Source):
You can put this solution on YOUR website!
.

x^2 + 3 = 38 + 2x  =============>


x^2 - 2x - 35 = 0


Factor left side


(x-7)*(x+5) = 0.


The roots are  x= 7  and  x= -5.      ANSWER


Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
equation to solve is x^2 + 3 = 38 + 2x
subtract 38 from both sides of the equation and subtract 2x from both sides of the equation to get:
x^2 + 3 - 38 - 2x = 0
combine liketerms to get:
x^2 - 35 - 2x = 0
rearrange the terms in descending order of degree to get:
x^2 - 2x - 35 = 0
factor this quadratic equation to get:
(x - 7) * (x + 5) = 0
solve for x to get:
x = 7 or x = -5
when x = 7, x^2 - 2x - 35 = 0 becomes 49 - 14 - 35 = 0 which becomes 49 - 49 = 0 which becomes 0 = 0, confirming that x = 7 is one of the solutions.
when x = -5, x^2 - 2x - 35 = 0 becomes 25 + 10 - 35 = 0 which becomes 35 - 35 = 0 which becomes 0 = 0, confirming that x = -5 is one of the solutions.
your solution is that x = 7 or x = -5.