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How do you solve #(2u - 7) ( 4+ u ) = 0#?

Answer 1

#u=7/2, u=-4#

Since #0# multiplied by anything is equal to #0#, we can say that it only requires one of the parenthesis to be equal to zero for the entire expression to be equal to zero.

Using this knowledge, we can setup two separate equations with each of the parenthesis being equal to #0#, knowing that both will be solutions to the original equation.

First parenthesis #2u-7=0#

#2ucancel(-7+7)=7#

#(cancel2u)/cancel2=7/2#

#u=7/2#

Second parenthesis #4+u=0#

#ucancel(+4-4)=-4#

#u=-4#

So we know that both #u=7/2# and #u=-4# are solutions to the equation.

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Answer 2

Kennedy Adams

To solve the equation (2u - 7)(4 + u) = 0:

Set each factor equal to zero and solve for u separately: a) 2u - 7 = 0 b) 4 + u = 0
Solve for u in each equation: a) 2u = 7 Divide both sides by 2: u = 7/2 or u = 3.5 b) u = -4
Combine the solutions: u = 3.5 or u = -4

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.