SOLUTION: Book is McGraw Hill - Beginning Algebra 6th Ed. by Hutchinson. Chapter 3 Section 3.4 exercise question at end of section number 78 Problem is to multiply the fraction (x/3

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Book is McGraw Hill - Beginning Algebra 6th Ed. by Hutchinson. Chapter 3 Section 3.4 exercise question at end of section number 78 Problem is to multiply the fraction (x/3      Log On


   

Question 118965: Book is McGraw Hill - Beginning Algebra 6th Ed. by Hutchinson.
Chapter 3 Section 3.4 exercise question at end of section number 78
Problem is to multiply the fraction
(x/3+3/4)(3x/4-3/5)
Found 2 solutions by checkley71, stanbon:
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
X/3+3/4
3X/4-3/5 NOW MULTIPLY
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(X/3)(3X/4)+(3/4)(3X/4)-(X/3)(3/5)-(3/4)(3/5)
X^2/4+9X/16-X/5-9/20
X^2/4+[(5*9X-16X)/16*5]-9/20
X^2/4+[(45X-16X)/80]-9/20
X^2/4+25X/80-9/20
[20X^2+25X-36)/80 ANSWER.
THIS EQUATION (20X^2+25X-36) IF REDUCED, NEEDS THE QUADRATIC EQUATION:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
(x/3+3/4)(3x/4-3/5)
Use FOIL to get:
F: x/3 * 3x/4 = x^2/4
O: x/3 * -3/5 = -x/5 = -16x/80
I: 3x/4 * 3/4 = 9x/16= 45x/80
L: (3/4)*-3/5 = -9/20
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Combine to get:
x^2/5 -29x/80 - 9/20
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Cheers,
Stan H.-