martin-gay, beginning algebra, 5ed 22 33 solve the following rational because no variable appears...
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33 Solve the following rational equation.EXAMPLE Because no variable appears in the denominator, no restrictions exist. The LCM of 5, 2, and 4 is 20, so we multiply both sides by 20: Using the multiplication principle to multiply both sides by the LCM. Parentheses are important! Using the distributive law. Be sure to multiply EACH term by the LCM.TRANSCRIPT
Martin-Gay, Beginning Algebra, 5ed 22
Martin-Gay, Beginning Algebra, 5ed 33
Solve the following rational equation.EXAMPLE1
5 2 4x x
Because no variable appears in the denominator, no restrictions exist. The LCM of 5, 2, and 4 is 20, so we multiply both sides by 20:
20 20 15 2 4x x
20 205 4
20 12
x x
Using the multiplication principle to multiply both sides by the LCM. Parentheses are important!
Using the distributive law. Be sure to multiply EACH term by the LCM.
Martin-Gay, Beginning Algebra, 5ed 44
4 10 5x x
6 5x
56
x
Simplifying and solving for x. If fractions remain, we have either made a mistake or have not used the LCM of the denominators.
We should check our solution, but no need to since we never make a mistake
Martin-Gay, Beginning Algebra, 5ed 55
SolveEXAMPLE
Restrictions: x cannot equal 0 LCD = 6x
671
35
x
671
35
x
xx
x 6671
356
xx 7610
x10
Martin-Gay, Beginning Algebra, 5ed 66
Restrictions: x cannot equal 3 LCD = 5(p + 3)
5( 3)p 5( 3)p
Martin-Gay, Beginning Algebra, 5ed 77
Restrictions: x cannot equal 0 LCD = x
Martin-Gay, Beginning Algebra, 5ed 88
Restrictions: x cannot equal 6 LCD = x 6
Martin-Gay, Beginning Algebra, 5ed 99
EXAMPLE Solve
2
2 5 41 1 1x x x
Restrictions: x cannot equal 1 or 1 LCD = (x 1)(x + 1)
( 1)( 1) ( 1)( 12 5 41 1 ( 1)( 1
))
x x x xx x x x
2( 1) 5( 1) 4x x
2 2 5 5 4x x
3 7 4x
3 3x
1x Because of the restriction above, 1 must be rejected as a solution. This equation has no solution.
Martin-Gay, Beginning Algebra, 5ed 1010
= (x 2)(x + 2) Restrictions: x cannot equal 2 or 2 LCD = (x 2)(x + 2)
Martin-Gay, Beginning Algebra, 5ed 1111
Restrictions: x cannot equal 1 or 3
Martin-Gay, Beginning Algebra, 5ed 1212