SOLUTION: can someone please help me i am no good with quadratics i have been practicing for a week and feel that i am wrong. x^2=-5x+8 (x+3)(x+4)=0 x=-3 x^2=16 x^2=16=0

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: can someone please help me i am no good with quadratics i have been practicing for a week and feel that i am wrong. x^2=-5x+8 (x+3)(x+4)=0 x=-3 x^2=16 x^2=16=0      Log On


   

Question 80815: can someone please help me i am no good with quadratics i have been practicing for a week and feel that i am wrong.
x^2=-5x+8
(x+3)(x+4)=0
x=-3
x^2=16
x^2=16=0
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
x^2 = -5x + 8
:
I'm not sure what you have got here, the above equation will not factor, anyway,
put in the ax^2 + bx + c = 0 form.
x^2 = -5x + 8
:
x^2 + 5x = 8; added 5x to both sides
x^2 + 5x - 8 = 0; subtracted 8 from both sides
:
There are no integer factors so use the quadratic formula:
Here it is step-by-step:
In this equation a = 1; b = 5; c = -8
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-5+%2B-+sqrt%28+5%5E2-4%2A1%2A-8+%29%29%2F%282%2A1%29+
x+=+%28-5+%2B-+sqrt%28+25+-%28-32%29+%29%29%2F%282%29+
x+=+%28-5+%2B-+sqrt%28+25+%2B+32+%29%29%2F%282%29+
x+=+%28-5+%2B-+sqrt%28+57+%29%29%2F%282%29+
x+=+%28-5+%2B-+7.55%29%2F%282%29+
Two solutions:
x+=+%28-5+%2B+7.55%29%2F%282%29+
x+=+%28%2B2.55%29%2F%282%29+
x = +1.275
and
x+=+%28-5+-+7.55%29%2F%282%29+
x+=+%28-12.55%29%2F%282%29+
x = -6.276
:
:
Are these supposed to be other problems; Let me know, and what you need help
with.
:
(x+3)(x+4)=0
x=-3
x^2=16
x^2=16=0