SOLUTION: solve using the quadratic formula 5x^2 + 8x = -3

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Question 74404This question is from textbook introduction and intermediate algebra
: solve using the quadratic formula
5x^2 + 8x = -3 This question is from textbook introduction and intermediate algebra

Answer by Cintchr(481) About Me  (Show Source):
You can put this solution on YOUR website!
+5x%5E2+%2B+8x+=+-3+
First you must get everything on the left side thereby setting the equation equal to zero.
+5x%5E2+%2B+8x+%2B+3+=+0+
This is now in the proper form.
A = 5
B = 8
C = 3
Plug these values into the Quadratic formula
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
+x+=+%28-8+%2B-+sqrt%288%5E2-4%2A5%2A3%29%29%2F%282%2A5%29+
square 8
+x+=+%28-8+%2B-+sqrt%2864-4%2A5%2A3%29%29%2F%282%2A5%29+
Multiply 4, 5 and 3
+x+=+%28-8+%2B-+sqrt%2864-60%29%29%2F%282%2A5%29+
Multiply 2 and 5
+x+=+%28-8+%2B-+sqrt%2864-60%29%29%2F10+
Subtract 64 and 60
+x+=+%28-8+%2B-+sqrt%284%29%29%2F10+
this is where it breaks into TWO problems
+x+=+%28-8+%2B+sqrt%284%29%29%2F10+ and +x+=+%28-8+-+sqrt%284%29%29%2F10+
Square root 4 in both problems
+x+=+%28-8+%2B+2%29%2F10+ and +x+=+%28-8+-+2%29%2F10+
work the Numerator in each fraction
+x+=+%28-6%29%2F10+ and +x+=+%28-10%29%2F10+
Reduce the fractions
+x+=+-3%2F5+ and +x+=+-1+