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Hello there!

If you can help me solve this equation step by step, that would be very helpful.

Thanks for stopping by!

Hello there! If you can help me solve this equation step by step, that would be very-example-1
User Udexter
by
5.7k points

2 Answers

5 votes


(x^2+3)^2 + 7x^2+21=-10

We want to convert this equation in terms of m, where
m = x^2+3

While solving this problem, I instantly noticed the
x^2+3 in the first term of the equation. Replace that with m.


m^2 + 7x^2+21=-10

Simplifying the rest is not as obvious. Using the distributive property, we can change
[7x^2+21] to
[7(x^2+3)]

Do you see the "m" in here? Look again if you don't.

Now we can simplify the equation to
m^2 + 7m=-10 and this cannot be simplified further.

I'm always happy to help someone who appreciates the help! :D

User MatWdo
by
6.1k points
2 votes

Answer:

m^2 +7(m) = -10

m^2 + 7m +10=0

(m+5) (m+2) =0

Are all acceptable versions of the equation

Explanation:

(x^2 +3) ^2 + 7x^2 +21 = -10

(x^2 +3)^2 + 7( x^2+3) = -10

Replace x^2 +3 with m

m^2 +7(m) = -10

Add 10 to each side

m^2 + 7m +10=-10+10

m^2 + 7m +10=0

Factor

(m+5) (m+2) =0

Using the zero product property

m=-5 m=-2

Replace m with x^2 +3

x^2+3 = -5 x^2 +3 =-2

Subtract 3 from each side

x^2+3-3 = -5-3 x^2 +3-3 =-2-3

x^2 = -8 x^2 = -5

x = ±2isqrt(2) x = ±i sqrt(5)

User MCS
by
6.6k points