solving equations involving absolute value
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|x+1|=x2-5. If x+1>0, that is, x>-1, then:

x+1=x2-5, x2-x-6=(x-3)(x+2)=0, so x-3=0, x=3; or x+2=0, x=-2. Therefore, since x must be greater than -1 we reject x=-2. That leaves x=3 as one solution. Plugging in x=3: |3+1|=4=9-5✔️ This confirms that x=3 is a solution

If x+1<0, x<-1 and -(x+1)=x2-5, -x-1=x2-5, x2+x-4=0, x=(-1±√(1+16))/2=1.5616 or -2.5616. So we reject the positive root because we need x+1 to be negative. That leaves x=-2.5616 as the other solution.

So the solutions are x=3 or -½(1+√17). CHECK: |-2.5616+1|=1.5616; x2-5=1.5616. This result checks out and confirms the second solution.

by Top Rated User (1.2m points)

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