138k views
25 votes
Find the roots 7x^2 + 46 = 32

1 Answer

1 vote

Answer:

i
√(2) (or no solution if you haven't learned about imaginary numbers yet)

Explanation:

The first thing you want to do is isolate x, or get x alone.

7x²+46=32

=> 7x²+46-46=32-46

=>7x²=-14

=>7x²÷7=-14÷7

=>x²=-2

If you have learned about imaginary numbers read on. If not, you have to realize that squaring any number can't result in a negative number. This means that there is no solution.

If you have learned about imaginary numbers, read on.

Now that you have x^2=-2, you can take the square root of both sides.

x=
√(-2)

Using a property about square roots (I don't know what it's called)

the equation becomes:

x=
√(-1)√(2)

And since
√(-1)=i, you can substitute in this value in to get x=i
√(2).

User Hendalst
by
5.0k points