SOLUTION: Solve the following equations: a: x^3-4x=0 b: 2x^2+7x-15=0

Question 148495: Solve the following equations:
a: x^3-4x=0
b: 2x^2+7x-15=0
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
a)

Start with the given equation.

Factor out the GCF x

Factor to get

Now set each factor equal to zero:

, or

Now solve for x for each factor:

, or

So the solutions of are , or

b)

Start with the given equation.

Let's use the quadratic formula to solve for x

Start with the quadratic formula

Plug in , , and

Square to get .

Multiply to get

Rewrite as

Add to to get

Multiply and to get .

Take the square root of to get .

or Break up the expression.

or Combine like terms.

or Simplify.

So our answers are or

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